157 files changed, 1286 insertions, 560 deletions

diff --git a/mailman/Utils.py b/mailman/Utils.py
index 26235d47d..10e201638 100644
--- a/mailman/Utils.py
+++ b/mailman/Utils.py
@@ -36,13 +36,14 @@ import email.Iterators
 
 from email.Errors import HeaderParseError
 from lazr.config import as_boolean
-from string import ascii_letters, digits, whitespace, Template
+from string import ascii_letters, digits, whitespace
 
 import mailman.templates
 
 from mailman import passwords
 from mailman.config import config
 from mailman.core import errors
+from mailman.utilities.string import expand
 
 
 AT = '@'
@@ -418,7 +419,7 @@ def UnobscureEmail(addr):
 class OuterExit(Exception):
     pass
 
-def findtext(templatefile, dict=None, raw=False, lang=None, mlist=None):
+def findtext(templatefile, raw_dict=None, raw=False, lang=None, mlist=None):
     # Make some text from a template file.  The order of searches depends on
     # whether mlist and lang are provided.  Once the templatefile is found,
     # string substitution is performed by interpolation in `dict'.  If `raw'
@@ -524,12 +525,8 @@ def findtext(templatefile, dict=None, raw=False, lang=None, mlist=None):
         fp.close()
         template = unicode(template, GetCharSet(lang), 'replace')
     text = template
-    if dict is not None:
-        try:
-            text = Template(template).safe_substitute(**dict)
-        except (TypeError, ValueError):
-            # The template is really screwed up
-            log.exception('broken template: %s', filename)
+    if raw_dict is not None:
+        text = expand(template, raw_dict)
     if raw:
         return text, filename
     return wrap(text), filename
diff --git a/mailman/app/bounces.py b/mailman/app/bounces.py
index 704921f38..875f615a5 100644
--- a/mailman/app/bounces.py
+++ b/mailman/app/bounces.py
@@ -17,6 +17,9 @@
 
 """Application level bounce handling."""
 
+from __future__ import unicode_literals
+
+__metaclass__ = type
 __all__ = [
     'bounce_message',
     ]
diff --git a/mailman/app/commands.py b/mailman/app/commands.py
index ef7b0a7c7..d7676af9c 100644
--- a/mailman/app/commands.py
+++ b/mailman/app/commands.py
@@ -17,6 +17,8 @@
 
 """Initialize the email commands."""
 
+from __future__ import unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'initialize',
@@ -37,6 +39,6 @@ def initialize():
             if not IEmailCommand.implementedBy(command_class):
                 continue
             assert command_class.name not in config.commands, (
-                'Duplicate email command "%s" found in %s' %
-                (command_class.name, module))
+                'Duplicate email command "{0}" found in {1}'.format(
+                    command_class.name, module))
             config.commands[command_class.name] = command_class()
diff --git a/mailman/app/lifecycle.py b/mailman/app/lifecycle.py
index 7b7daadf3..c57d7e1fc 100644
--- a/mailman/app/lifecycle.py
+++ b/mailman/app/lifecycle.py
@@ -17,6 +17,8 @@
 
 """Application level list creation."""
 
+from __future__ import unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'create_list',
@@ -83,7 +85,7 @@ def remove_list(fqdn_listname, mailing_list=None, archives=True):
         # Do the MTA-specific list deletion tasks
         module_name, class_name = config.mta.incoming.rsplit('.', 1)
         __import__(module_name)
-        getattr(sys.modules[module_name], class_name)().create(mlist)
+        getattr(sys.modules[module_name], class_name)().create(mailing_list)
         # Remove the list directory.
         removeables.append(os.path.join(config.LIST_DATA_DIR, fqdn_listname))
     # Remove any stale locks associated with the list.
diff --git a/mailman/app/membership.py b/mailman/app/membership.py
index 4d20be91e..4b9609469 100644
--- a/mailman/app/membership.py
+++ b/mailman/app/membership.py
@@ -17,6 +17,8 @@
 
 """Application support for membership management."""
 
+from __future__ import unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'add_member',
@@ -99,7 +101,7 @@ def add_member(mlist, address, realname, password, delivery_mode, language):
                 break
         else:
             raise AssertionError(
-                'User should have had linked address: %s', address)
+                'User should have had linked address: {0}'.format(address))
         # Create the member and set the appropriate preferences.
         member = address_obj.subscribe(mlist, MemberRole.member)
         member.preferences.preferred_language = language
diff --git a/mailman/app/moderator.py b/mailman/app/moderator.py
index 73a341534..b40a34344 100644
--- a/mailman/app/moderator.py
+++ b/mailman/app/moderator.py
@@ -17,6 +17,8 @@
 
 """Application support for moderators."""
 
+from __future__ import unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'handle_message',
@@ -144,7 +146,7 @@ def handle_message(mlist, id, action,
         # processing.
         config.switchboards['in'].enqueue(msg, _metadata=msgdata)
     else:
-        raise AssertionError('Unexpected action: %s' % action)
+        raise AssertionError('Unexpected action: {0}'.format(action))
     # Forward the message.
     if forward:
         # Get a copy of the original message from the message store.
@@ -257,7 +259,7 @@ def handle_subscription(mlist, id, action, comment=None):
                   delivery_mode, formataddr((realname, address)),
                   'via admin approval')
     else:
-        raise AssertionError('Unexpected action: %s' % action)
+        raise AssertionError('Unexpected action: {0}'.format(action))
     # Delete the request from the database.
     requestdb.delete_request(id)
 
@@ -313,7 +315,7 @@ def handle_unsubscription(mlist, id, action, comment=None):
             pass
         slog.info('%s: deleted %s', mlist.fqdn_listname, address)
     else:
-        raise AssertionError('Unexpected action: %s' % action)
+        raise AssertionError('Unexpected action: {0}'.format(action))
     # Delete the request from the database.
     requestdb.delete_request(id)
 
diff --git a/mailman/app/notifications.py b/mailman/app/notifications.py
index d60fe5fcf..9bef9998b 100644
--- a/mailman/app/notifications.py
+++ b/mailman/app/notifications.py
@@ -17,6 +17,8 @@
 
 """Sending notifications."""
 
+from __future__ import unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'send_admin_subscription_notice',
diff --git a/mailman/app/registrar.py b/mailman/app/registrar.py
index ad291891e..6a2abeba9 100644
--- a/mailman/app/registrar.py
+++ b/mailman/app/registrar.py
@@ -17,6 +17,8 @@
 
 """Implementation of the IUserRegistrar interface."""
 
+from __future__ import unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Registrar',
diff --git a/mailman/app/replybot.py b/mailman/app/replybot.py
index e9c303418..0537f6645 100644
--- a/mailman/app/replybot.py
+++ b/mailman/app/replybot.py
@@ -21,6 +21,9 @@
 # mailing list.  The reply governor should really apply site-wide per
 # recipient (I think).
 
+from __future__ import unicode_literals
+
+__metaclass__ = type
 __all__ = [
     'autorespond_to_sender',
     'can_acknowledge',
diff --git a/mailman/archiving/mailarchive.py b/mailman/archiving/mailarchive.py
index 334818204..a5eb27db0 100644
--- a/mailman/archiving/mailarchive.py
+++ b/mailman/archiving/mailarchive.py
@@ -17,6 +17,8 @@
 
 """The Mail-Archive.com archiver."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'MailArchive',
diff --git a/mailman/archiving/mhonarc.py b/mailman/archiving/mhonarc.py
index 76d022c92..949a79144 100644
--- a/mailman/archiving/mhonarc.py
+++ b/mailman/archiving/mhonarc.py
@@ -17,6 +17,8 @@
 
 """MHonArc archiver."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'MHonArc',
@@ -28,12 +30,12 @@ import logging
 import subprocess
 
 from base64 import b32encode
-from string import Template
 from urlparse import urljoin
 from zope.interface import implements
 
 from mailman.config import config
 from mailman.interfaces.archiver import IArchiver
+from mailman.utilities.string import expand
 
 
 log = logging.getLogger('mailman.archiver')
@@ -52,11 +54,11 @@ class MHonArc:
         """See `IArchiver`."""
         # XXX What about private MHonArc archives?
         web_host = config.domains[mlist.host_name].url_host
-        return Template(config.archiver.mhonarc.base_url).safe_substitute(
-            listname=mlist.fqdn_listname,
-            hostname=web_host,
-            fqdn_listname=mlist.fqdn_listname,
-            )
+        return expand(config.archiver.mhonarc.base_url,
+                      dict(listname=mlist.fqdn_listname,
+                           hostname=web_host,
+                           fqdn_listname=mlist.fqdn_listname,
+                           ))
 
     @staticmethod
     def permalink(mlist, msg):
@@ -83,8 +85,7 @@ class MHonArc:
         """See `IArchiver`."""
         substitutions = config.__dict__.copy()
         substitutions['listname'] = mlist.fqdn_listname
-        command = Template(config.archiver.mhonarc.command).safe_substitute(
-            substitutions)
+        command = expand(config.archiver.mhonarc.command, substitutions)
         proc = subprocess.Popen(
             command, stdout=subprocess.PIPE, stderr=subprocess.PIPE,
             shell=True)
diff --git a/mailman/archiving/pipermail.py b/mailman/archiving/pipermail.py
index d4969b9f6..4ee2e8dff 100644
--- a/mailman/archiving/pipermail.py
+++ b/mailman/archiving/pipermail.py
@@ -17,6 +17,8 @@
 
 """Pipermail archiver."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Pipermail',
@@ -26,7 +28,6 @@ __all__ = [
 import os
 
 from cStringIO import StringIO
-from string import Template
 from zope.interface import implements
 from zope.interface.interface import adapter_hooks
 
@@ -34,6 +35,7 @@ from mailman.Utils import makedirs
 from mailman.config import config
 from mailman.interfaces.archiver import IArchiver, IPipermailMailingList
 from mailman.interfaces.mailinglist import IMailingList
+from mailman.utilities.string import expand
 
 from mailman.Archiver.HyperArch import HyperArchive
 
@@ -94,12 +96,11 @@ class Pipermail:
             url = mlist.script_url('private') + '/index.html'
         else:
             web_host = config.domains[mlist.host_name].url_host
-            url = Template(config.archiver.pipermail.base_url).safe_substitute(
-                listname=mlist.fqdn_listname,
-                hostname=web_host,
-                fqdn_listname=mlist.fqdn_listname,
-                )
-        return url
+            return expand(config.archiver.pipermail.base_url,
+                          dict(listname=mlist.fqdn_listname,
+                               hostname=web_host,
+                               fqdn_listname=mlist.fqdn_listname,
+                               ))
 
     @staticmethod
     def permalink(mlist, message):
diff --git a/mailman/archiving/prototype.py b/mailman/archiving/prototype.py
index 8fbbe47c4..81163e184 100644
--- a/mailman/archiving/prototype.py
+++ b/mailman/archiving/prototype.py
@@ -17,6 +17,8 @@
 
 """Prototypical permalinking archiver."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Prototype',
diff --git a/mailman/chains/accept.py b/mailman/chains/accept.py
index d0c570c69..bd47f42c8 100644
--- a/mailman/chains/accept.py
+++ b/mailman/chains/accept.py
@@ -17,8 +17,12 @@
 
 """The terminal 'accept' chain."""
 
-__all__ = ['AcceptChain']
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
+__all__ = [
+    'AcceptChain',
+    ]
 
 import logging
 
diff --git a/mailman/chains/base.py b/mailman/chains/base.py
index f4e70c303..bcd946b40 100644
--- a/mailman/chains/base.py
+++ b/mailman/chains/base.py
@@ -17,6 +17,8 @@
 
 """Base class for terminal chains."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Chain',
@@ -78,7 +80,8 @@ class Chain:
     implements(IMutableChain)
 
     def __init__(self, name, description):
-        assert name not in config.chains, 'Duplicate chain name: %s' % name
+        assert name not in config.chains, (
+            'Duplicate chain name: {0}'.format(name))
         self.name = name
         self.description = description
         self._links = []
diff --git a/mailman/chains/builtin.py b/mailman/chains/builtin.py
index 1af1dd411..05912a2f2 100644
--- a/mailman/chains/builtin.py
+++ b/mailman/chains/builtin.py
@@ -17,6 +17,8 @@
 
 """The default built-in starting chain."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'BuiltInChain',
@@ -78,9 +80,7 @@ class BuiltInChain:
                 # Get the named rule.
                 rule = config.rules[rule_name]
                 # Get the chain, if one is defined.
-                if chain_name is None:
-                    chain = None
-                else:
-                    chain = config.chains[chain_name]
+                chain = (None if chain_name is None
+                         else config.chains[chain_name])
                 links.append(Link(rule, action, chain))
         return iter(self._cached_links)
diff --git a/mailman/chains/discard.py b/mailman/chains/discard.py
index 525505e36..1899e0340 100644
--- a/mailman/chains/discard.py
+++ b/mailman/chains/discard.py
@@ -17,8 +17,12 @@
 
 """The terminal 'discard' chain."""
 
-__all__ = ['DiscardChain']
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
+__all__ = [
+    'DiscardChain',
+    ]
 
 
 import logging
diff --git a/mailman/chains/headers.py b/mailman/chains/headers.py
index d76e48c50..2f85d78d0 100644
--- a/mailman/chains/headers.py
+++ b/mailman/chains/headers.py
@@ -17,6 +17,8 @@
 
 """The header-matching chain."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'HeaderMatchChain',
@@ -56,7 +58,7 @@ def make_link(entry):
         # We don't assert that the chain exists here because the jump
         # chain may not yet have been created.
     else:
-        raise AssertionError('Bad link description: %s' % entry)
+        raise AssertionError('Bad link description: {0}'.format(entry))
     rule = HeaderMatchRule(header, pattern)
     chain = config.chains[chain_name]
     return Link(rule, LinkAction.jump, chain)
@@ -73,9 +75,9 @@ class HeaderMatchRule:
     def __init__(self, header, pattern):
         self._header = header
         self._pattern = pattern
-        self.name = 'header-match-%002d' % HeaderMatchRule._count
+        self.name = 'header-match-{0:02}'.format(HeaderMatchRule._count)
         HeaderMatchRule._count += 1
-        self.description = u'%s: %s' % (header, pattern)
+        self.description = '{0}: {1}'.format(header, pattern)
         # XXX I think we should do better here, somehow recording that a
         # particular header matched a particular pattern, but that gets ugly
         # with RFC 2822 headers.  It also doesn't match well with the rule
diff --git a/mailman/chains/hold.py b/mailman/chains/hold.py
index f46733304..16238a541 100644
--- a/mailman/chains/hold.py
+++ b/mailman/chains/hold.py
@@ -17,6 +17,8 @@
 
 """The terminal 'hold' chain."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'HoldChain',
@@ -91,14 +93,14 @@ class HoldChain(TerminalChainBase):
             original_subject = _('(no subject)')
         else:
             original_subject = oneline(original_subject, charset)
-        substitutions = {
-            'listname'   : mlist.fqdn_listname,
-            'subject'    : original_subject,
-            'sender'     : sender,
-            'reason'     : 'XXX', #reason,
-            'confirmurl' : '%s/%s' % (mlist.script_url('confirm'), token),
-            'admindb_url': mlist.script_url('admindb'),
-            }
+        substitutions = dict(
+            listname    = mlist.fqdn_listname,
+            subject     = original_subject,
+            sender      = sender,
+            reason      = 'XXX', #reason,
+            confirmurl  = '{0}/{1}'.format(mlist.script_url('confirm'), token),
+            admindb_url = mlist.script_url('admindb'),
+            )
         # At this point the message is held, but now we have to craft at least
         # two responses.  The first will go to the original author of the
         # message and it will contain the token allowing them to approve or
@@ -167,7 +169,7 @@ also appear in the first line of the body of the reply.""")),
                 nmsg.attach(text)
                 nmsg.attach(MIMEMessage(msg))
                 nmsg.attach(MIMEMessage(dmsg))
-                nmsg.send(mlist, **{'tomoderators': 1})
+                nmsg.send(mlist, **dict(tomoderators=True))
         # Log the held message
         # XXX reason
         reason = 'n/a'
diff --git a/mailman/chains/reject.py b/mailman/chains/reject.py
index c7ec04fec..3faf563da 100644
--- a/mailman/chains/reject.py
+++ b/mailman/chains/reject.py
@@ -17,8 +17,12 @@
 
 """The terminal 'reject' chain."""
 
-__all__ = ['RejectChain']
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
+__all__ = [
+    'RejectChain',
+    ]
 
 
 import logging
diff --git a/mailman/config/__init__.py b/mailman/config/__init__.py
index 0611fc154..11f4f0c80 100644
--- a/mailman/config/__init__.py
+++ b/mailman/config/__init__.py
@@ -15,6 +15,10 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Mailman configuration package."""
+
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'config',
diff --git a/mailman/config/config.py b/mailman/config/config.py
index 44bb6d491..189917999 100644
--- a/mailman/config/config.py
+++ b/mailman/config/config.py
@@ -17,6 +17,8 @@
 
 """Configuration file loading and management."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Configuration',
diff --git a/mailman/constants.py b/mailman/constants.py
index d924b6722..39c4547f8 100644
--- a/mailman/constants.py
+++ b/mailman/constants.py
@@ -17,6 +17,9 @@
 
 """Various constants and enumerations."""
 
+from __future__ import unicode_literals
+
+__metaclass__ = type
 __all__ = [
     'SystemDefaultPreferences',
     ]
@@ -29,7 +32,7 @@ from mailman.interfaces.preferences import IPreferences
 
 
 
-class SystemDefaultPreferences(object):
+class SystemDefaultPreferences:
     implements(IPreferences)
 
     acknowledge_posts = False
diff --git a/mailman/core/chains.py b/mailman/core/chains.py
index 58935ed39..40b8c779f 100644
--- a/mailman/core/chains.py
+++ b/mailman/core/chains.py
@@ -17,6 +17,8 @@
 
 """Application support for chain processing."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'initialize',
@@ -56,7 +58,7 @@ def process(mlist, msg, msgdata, start_chain='built-in'):
         # we can capture a chain's link iterator in mid-flight.  This supports
         # the 'detour' link action
         try:
-            link = chain_iter.next()
+            link = next(chain_iter)
         except StopIteration:
             # This chain is exhausted.  Pop the last chain on the stack and
             # continue iterating through it.  If there's nothing left on the
@@ -90,7 +92,8 @@ def process(mlist, msg, msgdata, start_chain='built-in'):
             elif link.action is LinkAction.run:
                 link.function(mlist, msg, msgdata)
             else:
-                raise AssertionError('Bad link action: %s' % link.action)
+                raise AssertionError(
+                    'Bad link action: {0}'.format(link.action))
         else:
             # The rule did not match; keep going.
             if link.rule.record:
@@ -103,7 +106,7 @@ def initialize():
     for chain_class in (DiscardChain, HoldChain, RejectChain, AcceptChain):
         chain = chain_class()
         assert chain.name not in config.chains, (
-            'Duplicate chain name: %s' % chain.name)
+            'Duplicate chain name: {0}'.format(chain.name))
         config.chains[chain.name] = chain
     # Set up a couple of other default chains.
     chain = BuiltInChain()
diff --git a/mailman/core/errors.py b/mailman/core/errors.py
index 51803ae79..39401127e 100644
--- a/mailman/core/errors.py
+++ b/mailman/core/errors.py
@@ -17,6 +17,34 @@
 
 """Mailman errors."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'AlreadyReceivingDigests',
+    'AlreadyReceivingRegularDeliveries',
+    'BadDomainSpecificationError',
+    'BadPasswordSchemeError',
+    'CantDigestError',
+    'DiscardMessage',
+    'EmailAddressError',
+    'HandlerError',
+    'HoldMessage',
+    'HostileSubscriptionError',
+    'InvalidEmailAddress',
+    'LostHeldMessage',
+    'MailmanError',
+    'MailmanException',
+    'MemberError',
+    'MembershipIsBanned',
+    'MustDigestError',
+    'NotAMemberError',
+    'PasswordError',
+    'RejectMessage',
+    'SomeRecipientsFailed',
+    'SubscriptionError',
+    ]
+
 
 
 # Base class for all exceptions raised in Mailman (XXX except legacy string
diff --git a/mailman/core/initialize.py b/mailman/core/initialize.py
index c8b457d75..bb16f0036 100644
--- a/mailman/core/initialize.py
+++ b/mailman/core/initialize.py
@@ -24,6 +24,17 @@ line argument parsing, since some of the initialization behavior is controlled
 by the command line arguments.
 """
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'initialize',
+    'initialize_1',
+    'initialize_2',
+    'initialize_3',
+    ]
+
+
 import os
 
 from zope.interface.interface import adapter_hooks
diff --git a/mailman/core/logging.py b/mailman/core/logging.py
index 43abac78d..a18065965 100644
--- a/mailman/core/logging.py
+++ b/mailman/core/logging.py
@@ -17,7 +17,7 @@
 
 """Logging initialization, using Python's standard logging package."""
 
-from __future__ import absolute_import
+from __future__ import absolute_import, unicode_literals
 
 __metaclass__ = type
 __all__ = [
@@ -74,11 +74,10 @@ class ReopenableFileHandler(logging.Handler):
         stream = (self._stream if self._stream else sys.stderr)
         try:
             msg = self.format(record)
-            fs = '%s\n'
             try:
-                stream.write(fs % msg)
+                stream.write('{0}'.format(msg))
             except UnicodeError:
-                stream.write(fs % msg.encode('string-escape'))
+                stream.write('{0}'.format(msg.encode('string-escape')))
             self.flush()
         except:
             self.handleError(record)
diff --git a/mailman/core/pipelines.py b/mailman/core/pipelines.py
index 7be252388..8aae5cc25 100644
--- a/mailman/core/pipelines.py
+++ b/mailman/core/pipelines.py
@@ -17,6 +17,8 @@
 
 """Pipeline processor."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'initialize',
@@ -114,8 +116,8 @@ def initialize():
             handler = handler_class()
             verifyObject(IHandler, handler)
             assert handler.name not in config.handlers, (
-                'Duplicate handler "%s" found in %s' %
-                (handler.name, handler_finder))
+                'Duplicate handler "{0}" found in {1}'.format(
+                    handler.name, handler_finder))
             config.handlers[handler.name] = handler
     # Set up some pipelines.
     for pipeline_class in (BuiltInPipeline, VirginPipeline):
diff --git a/mailman/core/plugins.py b/mailman/core/plugins.py
index cce95fddd..e9ba26571 100644
--- a/mailman/core/plugins.py
+++ b/mailman/core/plugins.py
@@ -17,6 +17,13 @@
 
 """Get a requested plugin."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    ]
+
+
 import pkg_resources
 
 
@@ -36,7 +43,8 @@ def get_plugin(group):
     """
     entry_points = list(pkg_resources.iter_entry_points(group))
     if len(entry_points) == 0:
-        raise RuntimeError('No entry points found for group: %s' % group)
+        raise RuntimeError(
+            'No entry points found for group: {0}'.format(group))
     elif len(entry_points) == 1:
         # Okay, this is the one to use.
         return entry_points[0].load()
@@ -44,14 +52,15 @@ def get_plugin(group):
         # Find the one /not/ named 'stock'.
         entry_points = [ep for ep in entry_points if ep.name <> 'stock']
         if len(entry_points) == 0:
-            raise RuntimeError('No stock plugin found for group: %s' % group)
+            raise RuntimeError(
+                'No stock plugin found for group: {0}'.format(group))
         elif len(entry_points) == 2:
             raise RuntimeError('Too many stock plugins defined')
         else:
             raise AssertionError('Insanity')
         return entry_points[0].load()
     else:
-        raise RuntimeError('Too many plugins for group: %s' % group)
+        raise RuntimeError('Too many plugins for group: {0}'.format(group))
 
 
 
diff --git a/mailman/core/rules.py b/mailman/core/rules.py
index e272846d3..83e24dfa2 100644
--- a/mailman/core/rules.py
+++ b/mailman/core/rules.py
@@ -17,6 +17,8 @@
 
 """Various rule helpers"""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'initialize',
@@ -39,5 +41,6 @@ def initialize():
             rule = rule_class()
             verifyObject(IRule, rule)
             assert rule.name not in config.rules, (
-                'Duplicate rule "%s" found in %s' % (rule.name, rule_finder))
+                'Duplicate rule "{0}" found in {1}'.format(
+                    rule.name, rule_finder))
             config.rules[rule.name] = rule
diff --git a/mailman/database/__init__.py b/mailman/database/__init__.py
index 4c2a60e5d..8b7f584c2 100644
--- a/mailman/database/__init__.py
+++ b/mailman/database/__init__.py
@@ -15,6 +15,8 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'StockDatabase',
@@ -27,7 +29,6 @@ from locknix.lockfile import Lock
 from lazr.config import as_boolean
 from pkg_resources import resource_string
 from storm.locals import create_database, Store
-from string import Template
 from urlparse import urlparse
 from zope.interface import implements
 
@@ -41,6 +42,7 @@ from mailman.database.requests import Requests
 from mailman.database.usermanager import UserManager
 from mailman.database.version import Version
 from mailman.interfaces.database import IDatabase, SchemaVersionMismatchError
+from mailman.utilities.string import expand
 
 log = logging.getLogger('mailman.config')
 
@@ -86,7 +88,7 @@ class StockDatabase:
 
     def _create(self, debug):
         # Calculate the engine url.
-        url = Template(config.database.url).safe_substitute(config.paths)
+        url = expand(config.database.url, config.paths)
         log.debug('Database url: %s', url)
         # XXX By design of SQLite, database file creation does not honor
         # umask.  See their ticket #1193:
@@ -123,7 +125,7 @@ class StockDatabase:
         v = store.find(Version, component=u'schema').one()
         if not v:
             # Database has not yet been initialized
-            v = Version(component=u'schema',
+            v = Version(component='schema',
                         version=mailman.version.DATABASE_SCHEMA_VERSION)
             store.add(v)
         elif v.version <> mailman.version.DATABASE_SCHEMA_VERSION:
diff --git a/mailman/database/address.py b/mailman/database/address.py
index f9740deaf..528d3af51 100644
--- a/mailman/database/address.py
+++ b/mailman/database/address.py
@@ -15,6 +15,10 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Model for addresses."""
+
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Address',
@@ -64,10 +68,10 @@ class Address(Model):
         verified = ('verified' if self.verified_on else 'not verified')
         address_str = str(self)
         if self._original is None:
-            return '<Address: %s [%s] at %#x>' % (
+            return '<Address: {0} [{1}] at {2:#x}>'.format(
                 address_str, verified, id(self))
         else:
-            return '<Address: %s [%s] key: %s at %#x>' % (
+            return '<Address: {0} [{1}] key: {2} at {3:#x}>'.format(
                 address_str, verified, self.address, id(self))
 
     def subscribe(self, mailing_list, role):
diff --git a/mailman/database/language.py b/mailman/database/language.py
index 192c9a142..8adc5c4a5 100644
--- a/mailman/database/language.py
+++ b/mailman/database/language.py
@@ -15,6 +15,16 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Model for languages."""
+
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'Language',
+    ]
+
+
 from storm.locals import *
 from zope.interface import implements
 
diff --git a/mailman/database/listmanager.py b/mailman/database/listmanager.py
index 0a80a773e..346580eb9 100644
--- a/mailman/database/listmanager.py
+++ b/mailman/database/listmanager.py
@@ -17,6 +17,14 @@
 
 """A mailing list manager."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'ListManager',
+    ]
+
+
 import datetime
 
 from zope.interface import implements
diff --git a/mailman/database/mailinglist.py b/mailman/database/mailinglist.py
index 56caea296..fb45afe96 100644
--- a/mailman/database/mailinglist.py
+++ b/mailman/database/mailinglist.py
@@ -15,6 +15,16 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Model for mailing lists."""
+
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'MailingList',
+    ]
+
+
 import os
 import string
 
@@ -28,6 +38,7 @@ from mailman.database import roster
 from mailman.database.model import Model
 from mailman.database.types import Enum
 from mailman.interfaces.mailinglist import IMailingList, Personalization
+from mailman.utilities.string import expand
 
 
 SPACE = ' '
@@ -220,42 +231,42 @@ class MailingList(Model):
 
     @property
     def no_reply_address(self):
-        return '%s@%s' % (config.mailman.noreply_address, self.host_name)
+        return '{0}@{1}'.format(config.mailman.noreply_address, self.host_name)
 
     @property
     def owner_address(self):
-        return '%s-owner@%s' % (self.list_name, self.host_name)
+        return '{0}-owner@{1}'.format(self.list_name, self.host_name)
 
     @property
     def request_address(self):
-        return '%s-request@%s' % (self.list_name, self.host_name)
+        return '{0}-request@{1}'.format(self.list_name, self.host_name)
 
     @property
     def bounces_address(self):
-        return '%s-bounces@%s' % (self.list_name, self.host_name)
+        return '{0}-bounces@{1}'.format(self.list_name, self.host_name)
 
     @property
     def join_address(self):
-        return '%s-join@%s' % (self.list_name, self.host_name)
+        return '{0}-join@{1}'.format(self.list_name, self.host_name)
 
     @property
     def leave_address(self):
-        return '%s-leave@%s' % (self.list_name, self.host_name)
+        return '{0}-leave@{1}'.format(self.list_name, self.host_name)
 
     @property
     def subscribe_address(self):
-        return '%s-subscribe@%s' % (self.list_name, self.host_name)
+        return '{0}-subscribe@{1}'.format(self.list_name, self.host_name)
 
     @property
     def unsubscribe_address(self):
-        return '%s-unsubscribe@%s' % (self.list_name, self.host_name)
+        return '{0}-unsubscribe@{1}'.format(self.list_name, self.host_name)
 
     def confirm_address(self, cookie):
-        template = string.Template(config.mta.verp_confirm_format)
-        local_part = template.safe_substitute(
-            address = '%s-confirm' % self.list_name,
-            cookie  = cookie)
-        return '%s@%s' % (local_part, self.host_name)
+        local_part = expand(config.mta.verp_confirm_format, dict(
+            address = '{0}-confirm'.format(self.list_name),
+            cookie  = cookie))
+        return '{0}@{1}'.format(local_part, self.host_name)
 
     def __repr__(self):
-        return '<mailing list "%s" at %#x>' % (self.fqdn_listname, id(self))
+        return '<mailing list "{0}" at {1:#x}>'.format(
+            self.fqdn_listname, id(self))
diff --git a/mailman/database/member.py b/mailman/database/member.py
index 66d215e4d..22bf042f6 100644
--- a/mailman/database/member.py
+++ b/mailman/database/member.py
@@ -15,6 +15,10 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Model for members."""
+
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Member',
@@ -51,7 +55,7 @@ class Member(Model):
         self.is_moderated = False
 
     def __repr__(self):
-        return '<Member: %s on %s as %s>' % (
+        return '<Member: {0} on {1} as {2}>'.format(
             self.address, self.mailing_list, self.role)
 
     def _lookup(self, preference):
diff --git a/mailman/database/message.py b/mailman/database/message.py
index c7ec6bcf6..e77e11429 100644
--- a/mailman/database/message.py
+++ b/mailman/database/message.py
@@ -15,6 +15,11 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Model for messages."""
+
+
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Message',
diff --git a/mailman/database/messagestore.py b/mailman/database/messagestore.py
index 38c353172..d16fc93c4 100644
--- a/mailman/database/messagestore.py
+++ b/mailman/database/messagestore.py
@@ -15,6 +15,11 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Model for message stores."""
+
+
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'MessageStore',
@@ -54,8 +59,9 @@ class MessageStore:
         existing = config.db.store.find(Message,
                                         Message.message_id == message_id).one()
         if existing is not None:
-            raise ValueError('Message ID already exists in message store: %s',
-                             message_id)
+            raise ValueError(
+                'Message ID already exists in message store: {0}'.format(
+                    message_id))
         shaobj = hashlib.sha1(message_id)
         hash32 = base64.b32encode(shaobj.digest())
         del message['X-Message-ID-Hash']
@@ -86,8 +92,8 @@ class MessageStore:
                     # -1 says to use the highest protocol available.
                     pickle.dump(message, fp, -1)
                     break
-            except IOError, e:
-                if e.errno <> errno.ENOENT:
+            except IOError as error:
+                if error.errno <> errno.ENOENT:
                     raise
             os.makedirs(os.path.dirname(path))
         return hash32
diff --git a/mailman/database/model.py b/mailman/database/model.py
index 9a83002bd..85fa033c7 100644
--- a/mailman/database/model.py
+++ b/mailman/database/model.py
@@ -17,6 +17,8 @@
 
 """Base class for all database classes."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Model',
diff --git a/mailman/database/pending.py b/mailman/database/pending.py
index dc82085a2..75555b976 100644
--- a/mailman/database/pending.py
+++ b/mailman/database/pending.py
@@ -17,6 +17,8 @@
 
 """Implementations of the IPendable and IPending interfaces."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Pended',
@@ -122,8 +124,8 @@ class Pendings:
                 value = u'__builtin__.bool\1%s' % value
             elif type(value) is list:
                 # We expect this to be a list of strings.
-                value = u'mailman.database.pending.unpack_list\1%s' % (
-                    '\2'.join(value))
+                value = ('mailman.database.pending.unpack_list\1' +
+                         '\2'.join(value))
             keyval = PendedKeyValue(key=key, value=value)
             pending.key_values.add(keyval)
         config.db.store.add(pending)
@@ -135,7 +137,7 @@ class Pendings:
         if pendings.count() == 0:
             return None
         assert pendings.count() == 1, (
-            'Unexpected token count: %d' % pendings.count())
+            'Unexpected token count: {0}'.format(pendings.count()))
         pending = pendings[0]
         pendable = UnpendedPendable()
         # Find all PendedKeyValue entries that are associated with the pending
diff --git a/mailman/database/preferences.py b/mailman/database/preferences.py
index 244a1d2a7..f3ee55673 100644
--- a/mailman/database/preferences.py
+++ b/mailman/database/preferences.py
@@ -15,6 +15,16 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Model for preferences."""
+
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'Preferences',
+    ]
+
+
 from storm.locals import *
 from zope.interface import implements
 
@@ -37,4 +47,4 @@ class Preferences(Model):
     delivery_status = Enum()
 
     def __repr__(self):
-        return '<Preferences object at %#x>' % id(self)
+        return '<Preferences object at {0:#x}>'.format(id(self))
diff --git a/mailman/database/requests.py b/mailman/database/requests.py
index 812c5a0ab..249feb6b6 100644
--- a/mailman/database/requests.py
+++ b/mailman/database/requests.py
@@ -17,6 +17,8 @@
 
 """Implementations of the IRequests and IListRequests interfaces."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Requests',
diff --git a/mailman/database/roster.py b/mailman/database/roster.py
index fcebfb7f0..fc0a24c7d 100644
--- a/mailman/database/roster.py
+++ b/mailman/database/roster.py
@@ -22,6 +22,8 @@ the ones that fit a particular role.  These are used as the member, owner,
 moderator, and administrator roster filters.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'AdministratorRoster',
@@ -100,8 +102,9 @@ class AbstractRoster:
         elif results.count() == 1:
             return results[0]
         else:
-            raise AssertionError('Too many matching member results: %s' %
-                                 results.count())
+            raise AssertionError(
+                'Too many matching member results: {0}'.format(
+                    results.count()))
 
 
 
@@ -160,7 +163,7 @@ class AdministratorRoster(AbstractRoster):
             return results[0]
         else:
             raise AssertionError(
-                'Too many matching member results: %s' % results)
+                'Too many matching member results: {0}'.format(results))
 
 
 
@@ -262,5 +265,6 @@ class Memberships:
         elif results.count() == 1:
             return results[0]
         else:
-            raise AssertionError('Too many matching member results: %s' %
-                                 results.count())
+            raise AssertionError(
+                'Too many matching member results: {0}'.format(
+                    results.count()))
diff --git a/mailman/database/transaction.py b/mailman/database/transaction.py
index 4663f6110..d42562389 100644
--- a/mailman/database/transaction.py
+++ b/mailman/database/transaction.py
@@ -17,6 +17,8 @@
 
 """Transactional support."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'txn',
diff --git a/mailman/database/types.py b/mailman/database/types.py
index 17719c941..2f901fe49 100644
--- a/mailman/database/types.py
+++ b/mailman/database/types.py
@@ -15,6 +15,12 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Storm type conversions."""
+
+
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
 __all__ = [
     'Enum',
     ]
@@ -46,9 +52,10 @@ class _EnumVariable(Variable):
             return None
         if not to_db:
             return value
-        return '%s.%s:%d' % (value.enumclass.__module__,
-                             value.enumclass.__name__,
-                             int(value))
+        return '{0}.{1}:{2}'.format(
+            value.enumclass.__module__,
+            value.enumclass.__name__,
+            int(value))
 
 
 class Enum(SimpleProperty):
diff --git a/mailman/database/user.py b/mailman/database/user.py
index ec428f0a2..23701686b 100644
--- a/mailman/database/user.py
+++ b/mailman/database/user.py
@@ -15,6 +15,10 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Model for users."""
+
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'User',
@@ -48,7 +52,7 @@ class User(Model):
     preferences = Reference(preferences_id, 'Preferences.id')
 
     def __repr__(self):
-        return '<User "%s" at %#x>' % (self.real_name, id(self))
+        return '<User "{0}" at {1:#x}>'.format(self.real_name, id(self))
 
     def link(self, address):
         """See `IUser`."""
@@ -76,7 +80,7 @@ class User(Model):
         addrobj = config.db.store.find(Address, address=address).one()
         if addrobj is None:
             if real_name is None:
-                real_name = u''
+                real_name = ''
             addrobj = Address(address=address, real_name=real_name)
             addrobj.preferences = Preferences()
         # Link the address to the user if it is not already linked.
diff --git a/mailman/database/usermanager.py b/mailman/database/usermanager.py
index c30c40d12..3b0c8b534 100644
--- a/mailman/database/usermanager.py
+++ b/mailman/database/usermanager.py
@@ -17,6 +17,8 @@
 
 """A user manager."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'UserManager',
@@ -38,7 +40,7 @@ class UserManager(object):
 
     def create_user(self, address=None, real_name=None):
         user = User()
-        user.real_name = (u'' if real_name is None else real_name)
+        user.real_name = ('' if real_name is None else real_name)
         if address:
             addrobj = Address(address, user.real_name)
             addrobj.preferences = Preferences()
@@ -71,7 +73,7 @@ class UserManager(object):
             raise ExistingAddressError(found.original_address)
         assert addresses.count() == 0, 'Unexpected results'
         if real_name is None:
-            real_name = u''
+            real_name = ''
         # It's okay not to lower case the 'address' argument because the
         # constructor will do the right thing.
         address = Address(address, real_name)
diff --git a/mailman/database/version.py b/mailman/database/version.py
index 519c5438c..d15065395 100644
--- a/mailman/database/version.py
+++ b/mailman/database/version.py
@@ -15,6 +15,10 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Model class for version numbers."""
+
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Version',
diff --git a/mailman/docs/archivers.txt b/mailman/docs/archivers.txt
index 489e3f15b..ef36a25ac 100644
--- a/mailman/docs/archivers.txt
+++ b/mailman/docs/archivers.txt
@@ -77,10 +77,10 @@ archiver; by enabling it messages to public lists will get sent there
 automatically.
 
     >>> archiver = archivers['mail-archive']
-    >>> archiver.list_url(mlist)
-    'http://go.mail-archive.dev/test%40example.com'
-    >>> archiver.permalink(mlist, msg)
-    'http://go.mail-archive.dev/ZaXPPxRMM9_hFZL4vTRlQlBx8pc='
+    >>> print archiver.list_url(mlist)
+    http://go.mail-archive.dev/test%40example.com
+    >>> print archiver.permalink(mlist, msg)
+    http://go.mail-archive.dev/ZaXPPxRMM9_hFZL4vTRlQlBx8pc=
 
 To archive the message, the archiver actually mails the message to a special
 address at the Mail-Archive.
@@ -137,23 +137,23 @@ Additionally, this archiver can handle malformed Message-IDs.
     >>> mlist.archive_private = False
     >>> del msg['message-id']
     >>> msg['Message-ID'] = '12345>'
-    >>> archiver.permalink(mlist, msg)
-    'http://go.mail-archive.dev/bXvG32YzcDEIVDaDLaUSVQekfo8='
+    >>> print archiver.permalink(mlist, msg)
+    http://go.mail-archive.dev/bXvG32YzcDEIVDaDLaUSVQekfo8=
 
     >>> del msg['message-id']
     >>> msg['Message-ID'] = '<12345'
-    >>> archiver.permalink(mlist, msg)
-    'http://go.mail-archive.dev/9rockPrT1Mm-jOsLWS6_hseR_OY='
+    >>> print archiver.permalink(mlist, msg)
+    http://go.mail-archive.dev/9rockPrT1Mm-jOsLWS6_hseR_OY=
 
     >>> del msg['message-id']
     >>> msg['Message-ID'] = '12345'
-    >>> archiver.permalink(mlist, msg)
-    'http://go.mail-archive.dev/ZaXPPxRMM9_hFZL4vTRlQlBx8pc='
+    >>> print archiver.permalink(mlist, msg)
+    http://go.mail-archive.dev/ZaXPPxRMM9_hFZL4vTRlQlBx8pc=
 
     >>> del msg['message-id']
     >>> msg['Message-ID'] = '    12345    '
-    >>> archiver.permalink(mlist, msg)
-    'http://go.mail-archive.dev/ZaXPPxRMM9_hFZL4vTRlQlBx8pc='
+    >>> print archiver.permalink(mlist, msg)
+    http://go.mail-archive.dev/ZaXPPxRMM9_hFZL4vTRlQlBx8pc=
 
 
 MHonArc
@@ -162,8 +162,8 @@ MHonArc
 The MHonArc archiver <http://www.mhonarc.org> is also available.
 
     >>> archiver = archivers['mhonarc']
-    >>> archiver.name
-    'mhonarc'
+    >>> print archiver.name
+    mhonarc
 
 Messages sent to a local MHonArc instance are added to its archive via a
 subprocess call.
diff --git a/mailman/docs/chains.txt b/mailman/docs/chains.txt
index e9c5d74e4..b6e75e6e1 100644
--- a/mailman/docs/chains.txt
+++ b/mailman/docs/chains.txt
@@ -19,10 +19,10 @@ The Discard chain simply throws the message away.
     >>> chain = config.chains['discard']
     >>> verifyObject(IChain, chain)
     True
-    >>> chain.name
-    'discard'
-    >>> chain.description
-    u'Discard a message and stop processing.'
+    >>> print chain.name
+    discard
+    >>> print chain.description
+    Discard a message and stop processing.
 
     >>> from mailman.app.lifecycle import create_list
     >>> mlist = create_list(u'_xtest@example.com')
@@ -58,10 +58,10 @@ this action.
     >>> chain = config.chains['reject']
     >>> verifyObject(IChain, chain)
     True
-    >>> chain.name
-    'reject'
-    >>> chain.description
-    u'Reject/bounce a message and stop processing.'
+    >>> print chain.name
+    reject
+    >>> print chain.description
+    Reject/bounce a message and stop processing.
     >>> file_pos = fp.tell()
     >>> process(mlist, msg, {}, 'reject')
     >>> fp.seek(file_pos)
@@ -104,10 +104,10 @@ sender and the list moderators.
     >>> chain = config.chains['hold']
     >>> verifyObject(IChain, chain)
     True
-    >>> chain.name
-    'hold'
-    >>> chain.description
-    u'Hold a message and stop processing.'
+    >>> print chain.name
+    hold
+    >>> print chain.description
+    Hold a message and stop processing.
 
     >>> file_pos = fp.tell()
     >>> process(mlist, msg, {}, 'hold')
@@ -231,7 +231,7 @@ first item is a type code and the second item is a message id.
     [(u'id', ...), (u'type', u'held message')]
 
 The message itself is held in the message store.
- 
+
     >>> rkey, rdata = config.db.requests.get_list_requests(mlist).get_request(
     ...     data['id'])
     >>> msg = config.db.message_store.get_message_by_id(
@@ -256,10 +256,10 @@ processed and sent on to the list membership.
     >>> chain = config.chains['accept']
     >>> verifyObject(IChain, chain)
     True
-    >>> chain.name
-    'accept'
-    >>> chain.description
-    u'Accept a message.'
+    >>> print chain.name
+    accept
+    >>> print chain.description
+    Accept a message.
     >>> file_pos = fp.tell()
     >>> process(mlist, msg, {}, 'accept')
     >>> fp.seek(file_pos)
@@ -297,10 +297,10 @@ the Hold handler from previous versions of Mailman.
     >>> chain = config.chains['built-in']
     >>> verifyObject(IChain, chain)
     True
-    >>> chain.name
-    'built-in'
-    >>> chain.description
-    u'The built-in moderation chain.'
+    >>> print chain.name
+    built-in
+    >>> print chain.description
+    The built-in moderation chain.
 
 The previously created message is innocuous enough that it should pass through
 all default rules.  This message will end up in the pipeline queue.
@@ -320,7 +320,7 @@ all default rules.  This message will end up in the pipeline queue.
     X-Message-ID-Hash: RXJU4JL6N2OUN3OYMXXPPSCR7P7JE2BW
     X-Mailman-Rule-Misses: approved; emergency; loop; administrivia;
         implicit-dest;
-    	max-recipients; max-size; news-moderation; no-subject;
+        max-recipients; max-size; news-moderation; no-subject;
         suspicious-header
     <BLANKLINE>
     An important message.
@@ -331,7 +331,15 @@ hit and all rules that have missed.
 
     >>> sorted(qdata['rule_hits'])
     []
-    >>> sorted(qdata['rule_misses'])
-    ['administrivia', 'approved', 'emergency', 'implicit-dest', 'loop',
-     'max-recipients', 'max-size', 'news-moderation', 'no-subject',
-     'suspicious-header']
+    >>> for rule_name in sorted(qdata['rule_misses']):
+    ...     print rule_name
+    administrivia
+    approved
+    emergency
+    implicit-dest
+    loop
+    max-recipients
+    max-size
+    news-moderation
+    no-subject
+    suspicious-header
diff --git a/mailman/docs/pipelines.txt b/mailman/docs/pipelines.txt
index 205d210b1..0e6dad8e8 100644
--- a/mailman/docs/pipelines.txt
+++ b/mailman/docs/pipelines.txt
@@ -62,11 +62,11 @@ etc.
 And the message metadata has information about recipients and other stuff.
 However there are currently no recipients for this message.
 
-    >>> sorted(msgdata.items())
-    [('original_sender', u'aperson@example.com'),
-     ('origsubj', u'My first post'),
-     ('recips', set([])),
-     ('stripped_subject', <email.header.Header instance at ...>)]
+    >>> dump_msgdata(msgdata)
+    original_sender : aperson@example.com
+    origsubj        : My first post
+    recips          : set([])
+    stripped_subject: My first post
 
 And the message is now sitting in various other processing queues.
 
@@ -98,12 +98,13 @@ And the message is now sitting in various other processing queues.
     <BLANKLINE>
     First post!
     <BLANKLINE>
-    >>> print sorted(messages[0].msgdata.items())
-    [('_parsemsg', False), ('original_sender', u'aperson@example.com'),
-     ('origsubj', u'My first post'),
-     ('received_time', ...), ('recips', set([])),
-     ('stripped_subject', <email.header.Header instance at ...>),
-     ('version', 3)]
+    >>> dump_msgdata(messages[0].msgdata)
+    _parsemsg       : False
+    original_sender : aperson@example.com
+    origsubj        : My first post
+    recips          : set([])
+    stripped_subject: My first post
+    version         : 3
 
 This mailing list is not linked to an NNTP newsgroup, so there's nothing in
 the outgoing nntp queue.
@@ -141,13 +142,14 @@ This is the message that will actually get delivered to end recipients.
     <BLANKLINE>
     First post!
     <BLANKLINE>
-    >>> print sorted(messages[0].msgdata.items())
-    [('_parsemsg', False), ('listname', u'xtest@example.com'),
-     ('original_sender', u'aperson@example.com'),
-     ('origsubj', u'My first post'), ('received_time', ...),
-     ('recips', set([])),
-     ('stripped_subject', <email.header.Header instance at ...>),
-     ('version', 3)]
+    >>> dump_msgdata(messages[0].msgdata)
+    _parsemsg       : False
+    listname        : xtest@example.com
+    original_sender : aperson@example.com
+    origsubj        : My first post
+    recips          : set([])
+    stripped_subject: My first post
+    version         : 3
 
 There's now one message in the digest mailbox, getting ready to be sent.
 
diff --git a/mailman/docs/registration.txt b/mailman/docs/registration.txt
index 2e04f7ddf..d243188bc 100644
--- a/mailman/docs/registration.txt
+++ b/mailman/docs/registration.txt
@@ -158,13 +158,12 @@ message is sent to the user in order to verify the registered address.
     <BLANKLINE>
         postmaster@mail.example.com
     <BLANKLINE>
-    >>> sorted(qdata.items())
-    [('_parsemsg', False),
-     ('nodecorate', True),
-     ('received_time', ...),
-     ('recips', [u'aperson@example.com']),
-     ('reduced_list_headers', True),
-     ('version', 3)]
+    >>> dump_msgdata(qdata)
+    _parsemsg           : False
+    nodecorate          : True
+    recips              : [u'aperson@example.com']
+    reduced_list_headers: True
+    version             : 3
 
 The confirmation token shows up in several places, each of which provides an
 easy way for the user to complete the confirmation.  The token will always
diff --git a/mailman/docs/requests.txt b/mailman/docs/requests.txt
index aa6f031bd..87b835fb8 100644
--- a/mailman/docs/requests.txt
+++ b/mailman/docs/requests.txt
@@ -10,9 +10,10 @@ Here is a helper function for printing out held requests.
     >>> def show_holds(requests):
     ...     for request in requests.held_requests:
     ...         key, data = requests.get_request(request.id)
+    ...         print request.id, str(request.request_type), key
     ...         if data is not None:
-    ...             data = sorted(data.items())
-    ...         print request.id, str(request.request_type), key, data
+    ...             for key in sorted(data):
+    ...                 print '    {0}: {1}'.format(key, data[key])
 
 And another helper for displaying messages in the virgin queue.
 
@@ -80,10 +81,10 @@ And of course, now we can see that there are four requests being held.
     >>> requests.count_of(RequestType.unsubscription)
     1
     >>> show_holds(requests)
-    1 RequestType.held_message hold_1 None
-    2 RequestType.subscription hold_2 None
-    3 RequestType.unsubscription hold_3 None
-    4 RequestType.held_message hold_4 None
+    1 RequestType.held_message hold_1
+    2 RequestType.subscription hold_2
+    3 RequestType.unsubscription hold_3
+    4 RequestType.held_message hold_4
 
 If we try to hold a request with a bogus type, we get an exception.
 
@@ -101,11 +102,13 @@ We can hold requests with additional data.
     >>> requests.count
     5
     >>> show_holds(requests)
-    1 RequestType.held_message hold_1 None
-    2 RequestType.subscription hold_2 None
-    3 RequestType.unsubscription hold_3 None
-    4 RequestType.held_message hold_4 None
-    5 RequestType.held_message hold_5 [(u'bar', u'no'), (u'foo', u'yes')]
+    1 RequestType.held_message hold_1
+    2 RequestType.subscription hold_2
+    3 RequestType.unsubscription hold_3
+    4 RequestType.held_message hold_4
+    5 RequestType.held_message hold_5
+        bar: no
+        foo: yes
 
 
 Getting requests
@@ -116,8 +119,8 @@ of the request data we want.  This returns a 2-tuple of the key and data we
 originally held.
 
     >>> key, data = requests.get_request(2)
-    >>> key
-    u'hold_2'
+    >>> print key
+    hold_2
 
 Because we did not store additional data with request 2, it comes back as None
 now.
@@ -128,10 +131,11 @@ now.
 However, if we ask for a request that had data, we'd get it back now.
 
     >>> key, data = requests.get_request(5)
-    >>> key
-    u'hold_5'
-    >>> sorted(data.items())
-    [(u'bar', u'no'), (u'foo', u'yes')]
+    >>> print key
+    hold_5
+    >>> dump_msgdata(data)
+    bar: no
+    foo: yes
 
 If we ask for a request that is not in the database, we get None back.
 
@@ -150,12 +154,15 @@ over by type.
     >>> for request in requests.of_type(RequestType.held_message):
     ...     assert request.request_type is RequestType.held_message
     ...     key, data = requests.get_request(request.id)
+    ...     print request.id, key
     ...     if data is not None:
-    ...         data = sorted(data.items())
-    ...     print request.id, key, data
-    1 hold_1 None
-    4 hold_4 None
-    5 hold_5 [(u'bar', u'no'), (u'foo', u'yes')]
+    ...         for key in sorted(data):
+    ...             print '    {0}: {1}'.format(key, data[key])
+    1 hold_1
+    4 hold_4
+    5 hold_5
+    bar: no
+    foo: yes
 
 
 Deleting requests
@@ -168,10 +175,12 @@ database.
     >>> requests.count
     4
     >>> show_holds(requests)
-    1 RequestType.held_message hold_1 None
-    3 RequestType.unsubscription hold_3 None
-    4 RequestType.held_message hold_4 None
-    5 RequestType.held_message hold_5 [(u'bar', u'no'), (u'foo', u'yes')]
+    1 RequestType.held_message hold_1
+    3 RequestType.unsubscription hold_3
+    4 RequestType.held_message hold_4
+    5 RequestType.held_message hold_5
+        bar: no
+        foo: yes
     >>> print requests.get_request(2)
     None
 
@@ -286,14 +295,13 @@ The message can be rejected, meaning it is bounced back to the sender.
     <BLANKLINE>
         alist-owner@example.com
     <BLANKLINE>
-    >>> sorted(qdata.items())
-    [('_parsemsg', False),
-     ('listname', u'alist@example.com'),
-     ('nodecorate', True),
-     ('received_time', ...),
-     ('recips', [u'aperson@example.org']),
-     ('reduced_list_headers', True),
-     ('version', 3)]
+    >>> dump_msgdata(qdata)
+    _parsemsg           : False
+    listname            : alist@example.com
+    nodecorate          : True
+    recips              : [u'aperson@example.org']
+    reduced_list_headers: True
+    version             : 3
 
 Or the message can be approved.  This actually places the message back into
 the incoming queue for further processing, however the message metadata
@@ -313,11 +321,12 @@ indicates that the message has been approved.
     <BLANKLINE>
     Here's something important about our mailing list.
     <BLANKLINE>
-    >>> sorted(qdata.items())
-    [('_parsemsg', False),
-     (u'approved', True), ('moderator_approved', True),
-     (u'received_time', 123.45), (u'sender', u'aperson@example.com'),
-     ('version', 3)]
+    >>> dump_msgdata(qdata)
+    _parsemsg         : False
+    approved          : True
+    moderator_approved: True
+    sender            : aperson@example.com
+    version           : 3
 
 In addition to any of the above dispositions, the message can also be
 preserved for further study.  Ordinarily the message is removed from the
@@ -386,11 +395,13 @@ moderators.
     <BLANKLINE>
     Here's something important about our mailing list.
     <BLANKLINE>
-    >>> sorted(qdata.items())
-    [('_parsemsg', False), ('listname', u'alist@example.com'),
-    ('nodecorate', True), ('received_time', ...),
-    ('recips', [u'zperson@example.com']),
-    ('reduced_list_headers', True), ('version', 3)]
+    >>> dump_msgdata(qdata)
+    _parsemsg           : False
+    listname            : alist@example.com
+    nodecorate          : True
+    recips              : [u'zperson@example.com']
+    reduced_list_headers: True
+    version             : 3
 
 
 Holding subscription requests
@@ -454,13 +465,14 @@ queue when the message is held.
     <BLANKLINE>
     to process the request.
     <BLANKLINE>
-    >>> sorted(qdata.items())
-    [('_parsemsg', False),
-    ('listname', u'alist@example.com'),
-    ('nodecorate', True),
-    ('received_time', ...),
-    ('recips', [u'alist-owner@example.com']),
-    ('reduced_list_headers', True), ('tomoderators', True), ('version', 3)]
+    >>> dump_msgdata(qdata)
+    _parsemsg           : False
+    listname            : alist@example.com
+    nodecorate          : True
+    recips              : [u'alist-owner@example.com']
+    reduced_list_headers: True
+    tomoderators        : True
+    version             : 3
 
 Once held, the moderator can select one of several dispositions.  The most
 trivial is to simply defer a decision for now.
@@ -508,12 +520,13 @@ subscriber.
     <BLANKLINE>
         alist-owner@example.com
     <BLANKLINE>
-    >>> sorted(qdata.items())
-    [('_parsemsg', False), ('listname', u'alist@example.com'),
-    ('nodecorate', True),
-    ('received_time', ...),
-    ('recips', [u'cperson@example.org']),
-    ('reduced_list_headers', True), ('version', 3)]
+    >>> dump_msgdata(qdata)
+    _parsemsg           : False
+    listname            : alist@example.com
+    nodecorate          : True
+    recips              : [u'cperson@example.org']
+    reduced_list_headers: True
+    version             : 3
 
 The subscription can also be accepted.  This subscribes the address to the
 mailing list.
@@ -551,11 +564,14 @@ subscription and the fact that they may need to approve it.
     <BLANKLINE>
     to process the request.
     <BLANKLINE>
-    >>> sorted(qdata.items())
-    [('_parsemsg', False), ('listname', u'alist@example.com'),
-     ('nodecorate', True), ('received_time', ...),
-     ('recips', [u'alist-owner@example.com']),
-     ('reduced_list_headers', True), ('tomoderators', True), ('version', 3)]
+    >>> dump_msgdata(qdata)
+    _parsemsg           : False
+    listname            : alist@example.com
+    nodecorate          : True
+    recips              : [u'alist-owner@example.com']
+    reduced_list_headers: True
+    tomoderators        : True
+    version             : 3
 
 Accept the subscription request.
 
@@ -621,11 +637,14 @@ The welcome message is sent to the person who just subscribed.
     this email is not included here.  There is also a button on your
     options page that will send your current password to you.
     <BLANKLINE>
-    >>> sorted(welcome_qdata.items())
-    [('_parsemsg', False), ('listname', u'alist@example.com'),
-     ('nodecorate', True), ('received_time', ...),
-     ('recips', [u'fperson@example.org']),
-     ('reduced_list_headers', True), ('verp', False), ('version', 3)]
+    >>> dump_msgdata(welcome_qdata)
+    _parsemsg           : False
+    listname            : alist@example.com
+    nodecorate          : True
+    recips              : [u'fperson@example.org']
+    reduced_list_headers: True
+    verp                : False
+    version             : 3
 
 The admin message is sent to the moderators.
 
@@ -643,11 +662,14 @@ The admin message is sent to the moderators.
     Frank Person <fperson@example.org> has been successfully subscribed to
     A Test List.
     <BLANKLINE>
-    >>> sorted(admin_qdata.items())
-    [('_parsemsg', False), ('envsender', 'changeme@example.com'),
-     ('listname', u'alist@example.com'),
-     ('nodecorate', True), ('received_time', ...),
-     ('recips', []), ('reduced_list_headers', True), ('version', 3)]
+    >>> dump_msgdata(admin_qdata)
+    _parsemsg           : False
+    envsender           : changeme@example.com
+    listname            : alist@example.com
+    nodecorate          : True
+    recips              : []
+    reduced_list_headers: True
+    version             : 3
 
 Frank Person is now a member of the mailing list.
 
@@ -714,12 +736,14 @@ unsubscription holds can send the list's moderators an immediate notification.
     <BLANKLINE>
     to process the request.
     <BLANKLINE>
-    >>> sorted(qdata.items())
-    [('_parsemsg', False),
-     ('listname', u'alist@example.com'), ('nodecorate', True),
-     ('received_time', ...),
-     ('recips', [u'alist-owner@example.com']),
-     ('reduced_list_headers', True), ('tomoderators', True), ('version', 3)]
+    >>> dump_msgdata(qdata)
+    _parsemsg           : False
+    listname            : alist@example.com
+    nodecorate          : True
+    recips              : [u'alist-owner@example.com']
+    reduced_list_headers: True
+    tomoderators        : True
+    version             : 3
 
 There are now two addresses with held unsubscription requests.  As above, one
 of the actions we can take is to defer to the decision.
@@ -770,12 +794,14 @@ and the person remains a member of the mailing list.
     <BLANKLINE>
         alist-owner@example.com
     <BLANKLINE>
-    >>> sorted(qdata.items())
-    [('_parsemsg', False),
-     ('listname', u'alist@example.com'),
-     ('nodecorate', True), ('received_time', ...),
-     ('recips', [u'hperson@example.com']),
-     ('reduced_list_headers', True), ('version', 3)]
+    >>> dump_msgdata(qdata)
+    _parsemsg           : False
+    listname            : alist@example.com
+    nodecorate          : True
+    recips              : [u'hperson@example.com']
+    reduced_list_headers: True
+    version             : 3
+
     >>> mlist.members.get_member(u'hperson@example.com')
     <Member: hperson@example.com on alist@example.com as MemberRole.member>
 
@@ -823,12 +849,14 @@ The goodbye message...
     <BLANKLINE>
     So long!
     <BLANKLINE>
-    >>> sorted(goodbye_qdata.items())
-    [('_parsemsg', False),
-     ('listname', u'alist@example.com'),
-     ('nodecorate', True), ('received_time', ...),
-     ('recips', [u'gperson@example.com']),
-     ('reduced_list_headers', True), ('verp', False), ('version', 3)]
+    >>> dump_msgdata(goodbye_qdata)
+    _parsemsg           : False
+    listname            : alist@example.com
+    nodecorate          : True
+    recips              : [u'gperson@example.com']
+    reduced_list_headers: True
+    verp                : False
+    version             : 3
 
 ...and the admin message.
 
@@ -845,8 +873,11 @@ The goodbye message...
     <BLANKLINE>
     gperson@example.com has been removed from A Test List.
     <BLANKLINE>
-    >>> sorted(admin_qdata.items())
-    [('_parsemsg', False), ('envsender', 'changeme@example.com'),
-     ('listname', u'alist@example.com'),
-     ('nodecorate', True), ('received_time', ...),
-     ('recips', []), ('reduced_list_headers', True), ('version', 3)]
+    >>> dump_msgdata(admin_qdata)
+    _parsemsg           : False
+    envsender           : changeme@example.com
+    listname            : alist@example.com
+    nodecorate          : True
+    recips              : []
+    reduced_list_headers: True
+    version             : 3
diff --git a/mailman/domain.py b/mailman/domain.py
index 03c1ad39c..4a7bef755 100644
--- a/mailman/domain.py
+++ b/mailman/domain.py
@@ -17,6 +17,8 @@
 
 """Domains."""
 
+from __future__ import unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Domain',
@@ -50,8 +52,9 @@ class Domain:
             domain.  If not given, postmaster@`email_host` will be used.
         """
         self.email_host = email_host
-        self.base_url = (base_url if base_url is not None else
-                         'http://' + email_host)
+        self.base_url = (base_url
+                         if base_url is not None
+                         else 'http://' + email_host)
         self.description = description
         self.contact_address = (contact_address
                                 if contact_address is not None
@@ -60,7 +63,7 @@ class Domain:
 
     def confirm_address(self, token=''):
         """See `IDomain`."""
-        return 'confirm-%s@%s' % (token, self.email_host)
+        return 'confirm-{0}@{1}'.format(token, self.email_host)
 
     def confirm_url(self, token=''):
         """See `IDomain`."""
diff --git a/mailman/i18n.py b/mailman/i18n.py
index 278199535..d5e54ded2 100644
--- a/mailman/i18n.py
+++ b/mailman/i18n.py
@@ -17,6 +17,8 @@
 
 """Internationalization support."""
 
+from __future__ import unicode_literals
+
 __metaclass__ = type
 __all__ = [
     '_',
@@ -34,6 +36,7 @@ import string
 import gettext
 
 import mailman.messages
+from mailman.utilities.string import expand
 
 _translation = None
 _missing = object()
@@ -103,8 +106,8 @@ if _translation is None:
 
 def _(s):
     if s == '':
-        return u''
-    assert s, 'Cannot translate: %s' % s
+        return ''
+    assert s, 'Cannot translate: {0}'.format(s)
     # Do translation of the given string into the current language, and do PEP
     # 292 style $-string interpolation into the resulting string.
     #
@@ -120,8 +123,8 @@ def _(s):
     frame = sys._getframe(1)
     # A `safe' dictionary is used so we won't get an exception if there's a
     # missing key in the dictionary.
-    d = frame.f_globals.copy()
-    d.update(frame.f_locals)
+    raw_dict = frame.f_globals.copy()
+    raw_dict.update(frame.f_locals)
     # Mailman must be unicode safe internally (i.e. all strings inside Mailman
     # must be unicodes).  The translation service is one boundary to the
     # outside world, so to honor this constraint, make sure that all strings
@@ -129,10 +132,9 @@ def _(s):
     # dictionary values are 8-bit strings.
     tns = _translation.ugettext(s)
     charset = _translation.charset() or 'us-ascii'
-    for k, v in d.items():
-        if isinstance(v, str):
-            d[k] = unicode(v, charset, 'replace')
-    translated_string = Template(tns).safe_substitute(attrdict(d))
+    # Python requires ** dictionaries to have str, not unicode keys.  For our
+    # purposes, keys should always be ascii.  Values though should be unicode.
+    translated_string = expand(tns, attrdict(raw_dict), Template)
     if isinstance(translated_string, str):
         translated_string = unicode(translated_string, charset)
     return translated_string
@@ -191,5 +193,4 @@ def ctime(date):
 
     wday = daysofweek[wday]
     mon = months[mon]
-    return _('%(wday)s %(mon)s %(day)2i %(hh)02i:%(mm)02i:%(ss)02i '
-             '%(tzname)s %(year)04i')
+    return _('$wday $mon $day $hh:$mm:$ss $tzname $year')
diff --git a/mailman/inject.py b/mailman/inject.py
index 27edf827f..079236932 100644
--- a/mailman/inject.py
+++ b/mailman/inject.py
@@ -15,6 +15,8 @@
 # You should have received a copy of the GNU General Public License along with
 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
 
+from __future__ import unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'inject_message',
diff --git a/mailman/interact.py b/mailman/interact.py
index e8ff09b16..a30f22cee 100644
--- a/mailman/interact.py
+++ b/mailman/interact.py
@@ -17,6 +17,13 @@
 
 """Provide an interactive prompt, mimicking the Python interpreter."""
 
+from __future__ import unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'interact',
+    ]
+
 import os
 import sys
 import code
diff --git a/mailman/interfaces/address.py b/mailman/interfaces/address.py
index 802952774..968ded3ee 100644
--- a/mailman/interfaces/address.py
+++ b/mailman/interfaces/address.py
@@ -17,8 +17,19 @@
 
 """Interface for email address related information."""
 
-from zope.interface import Interface, Attribute
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'AddressAlreadyLinkedError',
+    'AddressError',
+    'AddressNotLinkedError',
+    'ExistingAddressError',
+    'IAddress',
+    ]
 
+
+from zope.interface import Interface, Attribute
 from mailman.interfaces.errors import MailmanError
 
 
diff --git a/mailman/interfaces/archiver.py b/mailman/interfaces/archiver.py
index c69b13427..35fee2c9e 100644
--- a/mailman/interfaces/archiver.py
+++ b/mailman/interfaces/archiver.py
@@ -17,12 +17,15 @@
 
 """Interface for archiving schemes."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'IArchiver',
     'IPipermailMailingList',
     ]
 
+
 from zope.interface import Interface, Attribute
 from mailman.interfaces.mailinglist import IMailingList
 
diff --git a/mailman/interfaces/chain.py b/mailman/interfaces/chain.py
index 2a18d3dea..2685b7980 100644
--- a/mailman/interfaces/chain.py
+++ b/mailman/interfaces/chain.py
@@ -17,6 +17,18 @@
 
 """Interfaces describing the basics of chains and links."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IChain',
+    'IChainIterator',
+    'IChainLink',
+    'IMutableChain',
+    'LinkAction',
+    ]
+
+
 from munepy import Enum
 from zope.interface import Interface, Attribute
 
diff --git a/mailman/interfaces/command.py b/mailman/interfaces/command.py
index 202d2a148..a9ad292f4 100644
--- a/mailman/interfaces/command.py
+++ b/mailman/interfaces/command.py
@@ -17,6 +17,16 @@
 
 """Interfaces defining email commands."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'ContinueProcessing',
+    'IEmailCommand',
+    'IEmailResults',
+    ]
+
+
 from munepy import Enum
 from zope.interface import Interface, Attribute
 
diff --git a/mailman/interfaces/database.py b/mailman/interfaces/database.py
index 27ab4bf83..4a9d6cde5 100644
--- a/mailman/interfaces/database.py
+++ b/mailman/interfaces/database.py
@@ -23,6 +23,8 @@ setup.py file as an entry point in the 'mailman.database' group with the name
 Mailman's back end.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'DatabaseError',
@@ -49,9 +51,9 @@ class SchemaVersionMismatchError(DatabaseError):
         self._got = got
 
     def __str__(self):
-        return (
-            'Incompatible database schema version (got: %d, expected: %d)'
-            % (self._got, DATABASE_SCHEMA_VERSION))
+        return ('Incompatible database schema version '
+                '(got: {0}, expected: {1})'.format(
+                    self._got, DATABASE_SCHEMA_VERSION))
 
 
 
diff --git a/mailman/interfaces/domain.py b/mailman/interfaces/domain.py
index 9ce402a70..8c2a27e79 100644
--- a/mailman/interfaces/domain.py
+++ b/mailman/interfaces/domain.py
@@ -17,6 +17,14 @@
 
 """Interface representing domains."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IDomain',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/errors.py b/mailman/interfaces/errors.py
index b174aa3cf..608193f7a 100644
--- a/mailman/interfaces/errors.py
+++ b/mailman/interfaces/errors.py
@@ -22,6 +22,13 @@ components.  More specific exceptions will be located in the relevant
 interfaces.
 """
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'MailmanError',
+    ]
+
 
 
 class MailmanError(Exception):
diff --git a/mailman/interfaces/handler.py b/mailman/interfaces/handler.py
index 9d03b7263..41d791d5d 100644
--- a/mailman/interfaces/handler.py
+++ b/mailman/interfaces/handler.py
@@ -17,6 +17,14 @@
 
 """Interface describing a pipeline handler."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IHandler',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/languages.py b/mailman/interfaces/languages.py
index d1cdf9f43..272cf4372 100644
--- a/mailman/interfaces/languages.py
+++ b/mailman/interfaces/languages.py
@@ -17,6 +17,15 @@
 
 """Interfaces for managing languages."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'ILanguage',
+    'ILanguageManager',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/listmanager.py b/mailman/interfaces/listmanager.py
index 6a774a04e..e7cdd9da7 100644
--- a/mailman/interfaces/listmanager.py
+++ b/mailman/interfaces/listmanager.py
@@ -17,6 +17,8 @@
 
 """Interface for list storage, deleting, and finding."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'IListManager',
diff --git a/mailman/interfaces/mailinglist.py b/mailman/interfaces/mailinglist.py
index 970c1ac07..cd7b11d64 100644
--- a/mailman/interfaces/mailinglist.py
+++ b/mailman/interfaces/mailinglist.py
@@ -17,12 +17,16 @@
 
 """Interface for a mailing list."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
 __all__ = [
     'IMailingList',
     'Personalization',
     'ReplyToMunging',
     ]
 
+
 from munepy import Enum
 from zope.interface import Interface, Attribute
 
diff --git a/mailman/interfaces/member.py b/mailman/interfaces/member.py
index 697117219..2e966879d 100644
--- a/mailman/interfaces/member.py
+++ b/mailman/interfaces/member.py
@@ -17,6 +17,7 @@
 
 """Interface describing the basics of a member."""
 
+from __future__ import absolute_import, unicode_literals
 
 __metaclass__ = type
 __all__ = [
@@ -78,7 +79,7 @@ class AlreadySubscribedError(SubscriptionError):
         self._role = role
 
     def __str__(self):
-        return '%s is already a %s of mailing list %s' % (
+        return '{0} is already a {1} of mailing list {2}'.format(
             self._address, self._role, self._fqdn_listname)
 
 
diff --git a/mailman/interfaces/messages.py b/mailman/interfaces/messages.py
index 0da595d0b..72efe960f 100644
--- a/mailman/interfaces/messages.py
+++ b/mailman/interfaces/messages.py
@@ -17,6 +17,15 @@
 
 """The message storage service."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IMessage',
+    'IMessageStore',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/mlistrequest.py b/mailman/interfaces/mlistrequest.py
index f348d617c..924421406 100644
--- a/mailman/interfaces/mlistrequest.py
+++ b/mailman/interfaces/mlistrequest.py
@@ -17,6 +17,14 @@
 
 """Interface for a web request accessing a mailing list."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IMailingListRequest',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/mta.py b/mailman/interfaces/mta.py
index 5e647cfb2..a8c794750 100644
--- a/mailman/interfaces/mta.py
+++ b/mailman/interfaces/mta.py
@@ -17,6 +17,8 @@
 
 """Interface for mail transport agent integration."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'IMailTransportAgent',
diff --git a/mailman/interfaces/pending.py b/mailman/interfaces/pending.py
index 7fcde07ad..0e43278e0 100644
--- a/mailman/interfaces/pending.py
+++ b/mailman/interfaces/pending.py
@@ -22,6 +22,17 @@ maps these events to a unique hash that can be used as a token for end user
 confirmation.
 """
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IPendable',
+    'IPended',
+    'IPendedKeyValue',
+    'IPendings',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/permissions.py b/mailman/interfaces/permissions.py
index fb36f35b5..7613064f5 100644
--- a/mailman/interfaces/permissions.py
+++ b/mailman/interfaces/permissions.py
@@ -17,6 +17,14 @@
 
 """Interfaces for various permissions."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IPostingPermission',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/pipeline.py b/mailman/interfaces/pipeline.py
index a95fb7628..0268693b7 100644
--- a/mailman/interfaces/pipeline.py
+++ b/mailman/interfaces/pipeline.py
@@ -17,6 +17,14 @@
 
 """Interface for describing pipelines."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IPipeline',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/preferences.py b/mailman/interfaces/preferences.py
index fbd81c801..9aeed8496 100644
--- a/mailman/interfaces/preferences.py
+++ b/mailman/interfaces/preferences.py
@@ -17,6 +17,14 @@
 
 """Interface for preferences."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IPreferences',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/registrar.py b/mailman/interfaces/registrar.py
index d6c174d85..d90966e2d 100644
--- a/mailman/interfaces/registrar.py
+++ b/mailman/interfaces/registrar.py
@@ -22,6 +22,8 @@ etc. than the IUserManager.  The latter does no validation, syntax checking,
 or confirmation, while this interface does.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'IRegistrar',
diff --git a/mailman/interfaces/requests.py b/mailman/interfaces/requests.py
index b9c0802f4..e3e316fa0 100644
--- a/mailman/interfaces/requests.py
+++ b/mailman/interfaces/requests.py
@@ -21,6 +21,16 @@ The request database handles events that must be approved by the list
 moderators, such as subscription requests and held messages.
 """
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IListRequests',
+    'IRequests',
+    'RequestType',
+    ]
+
+
 from munepy import Enum
 from zope.interface import Interface, Attribute
 
diff --git a/mailman/interfaces/roster.py b/mailman/interfaces/roster.py
index f7b2125fd..9fb648be1 100644
--- a/mailman/interfaces/roster.py
+++ b/mailman/interfaces/roster.py
@@ -17,6 +17,14 @@
 
 """Interface for a roster of members."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IRoster',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/rules.py b/mailman/interfaces/rules.py
index 24501848f..632cc85de 100644
--- a/mailman/interfaces/rules.py
+++ b/mailman/interfaces/rules.py
@@ -17,6 +17,14 @@
 
 """Interface describing the basics of rules."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IRule',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/runner.py b/mailman/interfaces/runner.py
index 500efd541..e923e099b 100644
--- a/mailman/interfaces/runner.py
+++ b/mailman/interfaces/runner.py
@@ -17,6 +17,14 @@
 
 """Interface for queue runners."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IRunner',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/styles.py b/mailman/interfaces/styles.py
index 7cc0e50e8..e70050f02 100644
--- a/mailman/interfaces/styles.py
+++ b/mailman/interfaces/styles.py
@@ -17,6 +17,8 @@
 
 """Interfaces for list styles."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'DuplicateStyleError',
diff --git a/mailman/interfaces/switchboard.py b/mailman/interfaces/switchboard.py
index 96cf1aea2..866093d12 100644
--- a/mailman/interfaces/switchboard.py
+++ b/mailman/interfaces/switchboard.py
@@ -17,6 +17,14 @@
 
 """Interface for switchboards."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'ISwitchboard',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/user.py b/mailman/interfaces/user.py
index 8824a2d7c..5c3ff58cd 100644
--- a/mailman/interfaces/user.py
+++ b/mailman/interfaces/user.py
@@ -17,6 +17,14 @@
 
 """Interface describing the basics of a user."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IUser',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/interfaces/usermanager.py b/mailman/interfaces/usermanager.py
index 7454faea8..41bec49ba 100644
--- a/mailman/interfaces/usermanager.py
+++ b/mailman/interfaces/usermanager.py
@@ -17,6 +17,14 @@
 
 """Interface describing a user manager service."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'IUserManager',
+    ]
+
+
 from zope.interface import Interface, Attribute
 
 
diff --git a/mailman/languages.py b/mailman/languages.py
index 27e2353de..7e093bc62 100644
--- a/mailman/languages.py
+++ b/mailman/languages.py
@@ -17,6 +17,13 @@
 
 """Language manager."""
 
+from __future__ import unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'LanguageManager',
+    ]
+
 from zope.interface import implements
 from mailman.interfaces.languages import ILanguageManager
 
diff --git a/mailman/mta/null.py b/mailman/mta/null.py
index 058ecb548..07cb7a869 100644
--- a/mailman/mta/null.py
+++ b/mailman/mta/null.py
@@ -20,17 +20,19 @@
 Exim one example of an MTA that Just Works.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
-    'LMTP',
+    'NullMTA',
     ]
 
 
 from zope.interface import implements
-
 from mailman.interfaces.mta import IMailTransportAgent
 
 
+
 class NullMTA:
     """Null MTA that just satisfies the interface."""
 
diff --git a/mailman/mta/postfix.py b/mailman/mta/postfix.py
index da265fecf..4cb172d99 100644
--- a/mailman/mta/postfix.py
+++ b/mailman/mta/postfix.py
@@ -17,6 +17,8 @@
 
 """Creation/deletion hooks for the Postfix MTA."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'LMTP',
diff --git a/mailman/mta/smtp_direct.py b/mailman/mta/smtp_direct.py
index b82fb9227..717b3eb90 100644
--- a/mailman/mta/smtp_direct.py
+++ b/mailman/mta/smtp_direct.py
@@ -26,6 +26,8 @@ Note: This file only handles single threaded delivery.  See SMTPThreaded.py
 for a threaded implementation.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'SMTPDirect',
@@ -41,7 +43,6 @@ import smtplib
 from email.Charset import Charset
 from email.Header import Header
 from email.Utils import formataddr
-from string import Template
 from zope.interface import implements
 
 from mailman import Utils
@@ -50,6 +51,7 @@ from mailman.core import errors
 from mailman.i18n import _
 from mailman.interfaces.handler import IHandler
 from mailman.interfaces.mailinglist import Personalization
+from mailman.utilities.string import expand
 
 
 DOT = '.'
@@ -61,43 +63,43 @@ log = logging.getLogger('mailman.smtp')
 # Manage a connection to the SMTP server
 class Connection:
     def __init__(self):
-        self.__conn = None
+        self._conn = None
 
-    def __connect(self):
-        self.__conn = smtplib.SMTP()
+    def _connect(self):
+        self._conn = smtplib.SMTP()
         host = config.mta.smtp_host
         port = int(config.mta.smtp_port)
         log.debug('Connecting to %s:%s', host, port)
-        self.__conn.connect(host, port)
-        self.__numsessions = int(config.mta.max_sessions_per_connection)
+        self._conn.connect(host, port)
+        self._numsessions = int(config.mta.max_sessions_per_connection)
 
     def sendmail(self, envsender, recips, msgtext):
-        if self.__conn is None:
-            self.__connect()
+        if self._conn is None:
+            self._connect()
         try:
-            results = self.__conn.sendmail(envsender, recips, msgtext)
+            results = self._conn.sendmail(envsender, recips, msgtext)
         except smtplib.SMTPException:
             # For safety, close this connection.  The next send attempt will
             # automatically re-open it.  Pass the exception on up.
             self.quit()
             raise
         # This session has been successfully completed.
-        self.__numsessions -= 1
+        self._numsessions -= 1
         # By testing exactly for equality to 0, we automatically handle the
         # case for SMTP_MAX_SESSIONS_PER_CONNECTION <= 0 meaning never close
         # the connection.  We won't worry about wraparound <wink>.
-        if self.__numsessions == 0:
+        if self._numsessions == 0:
             self.quit()
         return results
 
     def quit(self):
-        if self.__conn is None:
+        if self._conn is None:
             return
         try:
-            self.__conn.quit()
+            self._conn.quit()
         except smtplib.SMTPException:
             pass
-        self.__conn = None
+        self._conn = None
 
 
 
@@ -123,7 +125,7 @@ def process(mlist, msg, msgdata):
     if (not msgdata.has_key('personalize') or msgdata['personalize']) and (
            msgdata.get('verp') or mlist.personalize <> Personalization.none):
         chunks = [[recip] for recip in recips]
-        msgdata['personalize'] = 1
+        msgdata['personalize'] = True
         deliveryfunc = verpdeliver
     elif int(config.mta.max_recipients) <= 0:
         chunks = [recips]
@@ -192,13 +194,11 @@ def process(mlist, msg, msgdata):
     # Log this message.
     template = config.logging.smtp.every
     if template != 'no':
-        template = Template(template)
-        log.info('%s', template.safe_substitute(substitutions))
+        log.info('%s', expand(template, substitutions))
     if refused:
         template = config.logging.smtp.refused
         if template != 'no':
-            template = Template(template)
-            log.info('%s', template.safe_substitute(substitutions))
+            log.info('%s', expand(template, substitutions))
     else:
         # Log the successful post, but if it was not destined to the mailing
         # list (e.g. to the owner or admin), print the actual recipients
@@ -209,8 +209,7 @@ def process(mlist, msg, msgdata):
             substitutions['recips'] = COMMA.join(recips)
         template = config.logging.smtp.success
         if template != 'no':
-            template = Template(template)
-            log.info('%s', template.safe_substitute(substitutions))
+            log.info('%s', expand(template, substitutions))
     # Process any failed deliveries.
     tempfailures = []
     permfailures = []
@@ -238,8 +237,7 @@ def process(mlist, msg, msgdata):
                 smtpcode    = code,
                 smtpmsg     = smtpmsg,
                 )
-            template = Template(template)
-            log.info('%s', template.safe_substitute(substitutions))
+            log.info('%s', expand(template, substitutions))
     # Return the results
     if tempfailures or permfailures:
         raise errors.SomeRecipientsFailed(tempfailures, permfailures)
@@ -315,9 +313,9 @@ def verpdeliver(mlist, msg, msgdata, envsender, failures, conn):
                 # this recipient.
                 log.info('Skipping VERP delivery to unqual recip: %s', recip)
                 continue
-            envsender = Template(config.mta.verp_format).safe_substitute(
+            envsender = expand(config.mta.verp_format, dict(
                 bounces=bmailbox, mailbox=rmailbox,
-                host=DOT.join(rdomain)) + '@' + DOT.join(bdomain)
+                host=DOT.join(rdomain))) + '@' + DOT.join(bdomain)
         if mlist.personalize == Personalization.full:
             # When fully personalizing, we want the To address to point to the
             # recipient, not to the mailing list
@@ -378,28 +376,28 @@ def bulkdeliver(mlist, msg, msgdata, envsender, failures, conn):
     try:
         # Send the message
         refused = conn.sendmail(envsender, recips, msgtext)
-    except smtplib.SMTPRecipientsRefused, e:
-        log.error('%s recipients refused: %s', msgid, e)
-        refused = e.recipients
-    except smtplib.SMTPResponseException, e:
+    except smtplib.SMTPRecipientsRefused as error:
+        log.error('%s recipients refused: %s', msgid, error)
+        refused = error.recipients
+    except smtplib.SMTPResponseException as error:
         log.error('%s SMTP session failure: %s, %s',
-                   msgid, e.smtp_code, e.smtp_error)
+                   msgid, error.smtp_code, error.smtp_error)
         # If this was a permanent failure, don't add the recipients to the
         # refused, because we don't want them to be added to failures.
         # Otherwise, if the MTA rejects the message because of the message
         # content (e.g. it's spam, virii, or has syntactic problems), then
         # this will end up registering a bounce score for every recipient.
         # Definitely /not/ what we want.
-        if e.smtp_code < 500 or e.smtp_code == 552:
+        if error.smtp_code < 500 or error.smtp_code == 552:
             # It's a temporary failure
             for r in recips:
-                refused[r] = (e.smtp_code, e.smtp_error)
-    except (socket.error, IOError, smtplib.SMTPException), e:
+                refused[r] = (error.smtp_code, error.smtp_error)
+    except (socket.error, IOError, smtplib.SMTPException) as error:
         # MTA not responding, or other socket problems, or any other kind of
         # SMTPException.  In that case, nothing got delivered, so treat this
         # as a temporary failure.
-        log.error('%s low level smtp error: %s', msgid, e)
-        error = str(e)
+        log.error('%s low level smtp error: %s', msgid, error)
+        error = str(error)
         for r in recips:
             refused[r] = (-1, error)
     failures.update(refused)
diff --git a/mailman/options.py b/mailman/options.py
index 8d752bfb5..5431b2da8 100644
--- a/mailman/options.py
+++ b/mailman/options.py
@@ -17,10 +17,13 @@
 
 """Common argument parsing."""
 
+from __future__ import unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Options',
     'SingleMailingListOptions',
+    'MultipleMailingListOptions',
     ]
 
 
@@ -44,13 +47,13 @@ def check_unicode(option, opt, value):
         return value.decode(sys.getdefaultencoding())
     except UnicodeDecodeError:
         raise OptionValueError(
-            'option %s: Cannot decode: %r' % (opt, value))
+            'option {0}: Cannot decode: {1}'.format(opt, value))
 
 
 def check_yesno(option, opt, value):
     value = value.lower()
     if value not in ('yes', 'no', 'y', 'n'):
-        raise OptionValueError('option s: invalid: %r' % (opt, value))
+        raise OptionValueError('option {0}: invalid: {1}'.format(opt, value))
     return value[0] == 'y'
 
 
@@ -92,8 +95,9 @@ class Options:
 
     def add_common_options(self):
         """Add options common to all scripts."""
+        # Python requires str types here.
         self.parser.add_option(
-            '-C', '--config',
+            str('-C'), str('--config'),
             help=_('Alternative configuration file to use'))
 
     def initialize(self, propagate_logs=None):
@@ -135,6 +139,5 @@ class MultipleMailingListOptions(Options):
         self.parser.add_option(
             '-l', '--listname',
             default=[], action='append', dest='listnames', type='unicode',
-            help=("""\
+            help=_("""\
 A mailing list name.  It is okay to have multiple --listname options."""))
-
diff --git a/mailman/passwords.py b/mailman/passwords.py
index 9ce403cc7..0c8284c1c 100644
--- a/mailman/passwords.py
+++ b/mailman/passwords.py
@@ -20,6 +20,16 @@
 Represents passwords using RFC 2307 syntax (as best we can tell).
 """
 
+from __future__ import unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'Schemes',
+    'make_secret',
+    'check_response',
+    ]
+
+
 import os
 import re
 import hmac
@@ -35,16 +45,10 @@ from mailman.core import errors
 SALT_LENGTH = 20 # bytes
 ITERATIONS  = 2000
 
-__all__ = [
-    'Schemes',
-    'make_secret',
-    'check_response',
-    ]
-
 
 
-class PasswordScheme(object):
-    TAG = ''
+class PasswordScheme:
+    TAG = b''
 
     @staticmethod
     def make_secret(password):
@@ -63,11 +67,11 @@ class PasswordScheme(object):
 
 
 class NoPasswordScheme(PasswordScheme):
-    TAG = 'NONE'
+    TAG = b'NONE'
 
     @staticmethod
     def make_secret(password):
-        return ''
+        return b''
 
     @staticmethod
     def check_response(challenge, response):
@@ -76,7 +80,7 @@ class NoPasswordScheme(PasswordScheme):
 
 
 class ClearTextPasswordScheme(PasswordScheme):
-    TAG = 'CLEARTEXT'
+    TAG = b'CLEARTEXT'
 
     @staticmethod
     def make_secret(password):
@@ -89,7 +93,7 @@ class ClearTextPasswordScheme(PasswordScheme):
 
 
 class SHAPasswordScheme(PasswordScheme):
-    TAG = 'SHA'
+    TAG = b'SHA'
 
     @staticmethod
     def make_secret(password):
@@ -104,7 +108,7 @@ class SHAPasswordScheme(PasswordScheme):
 
 
 class SSHAPasswordScheme(PasswordScheme):
-    TAG = 'SSHA'
+    TAG = b'SSHA'
 
     @staticmethod
     def make_secret(password):
@@ -130,7 +134,7 @@ class PBKDF2PasswordScheme(PasswordScheme):
     # This is a bit nasty if we wanted a different prf or iterations.  OTOH,
     # we really have no clue what the standard LDAP-ish specification for
     # those options is.
-    TAG = 'PBKDF2 SHA %d' % ITERATIONS
+    TAG = b'PBKDF2 SHA {0}'.format(ITERATIONS)
 
     @staticmethod
     def _pbkdf2(password, salt, iterations):
@@ -141,13 +145,13 @@ class PBKDF2PasswordScheme(PasswordScheme):
         """
         h = hmac.new(password, None, hashlib.sha1)
         prf = h.copy()
-        prf.update(salt + '\x00\x00\x00\x01')
-        T = U = array('l', prf.digest())
+        prf.update(salt + b'\x00\x00\x00\x01')
+        T = U = array(b'l', prf.digest())
         while iterations:
             prf = h.copy()
             prf.update(U.tostring())
-            U = array('l', prf.digest())
-            T = array('l', (t ^ u for t, u in zip(T, U)))
+            U = array(b'l', prf.digest())
+            T = array(b'l', (t ^ u for t, u in zip(T, U)))
             iterations -= 1
         return T.tostring()
 
@@ -167,7 +171,7 @@ class PBKDF2PasswordScheme(PasswordScheme):
     def check_response(challenge, response, prf, iterations):
         # Decode the challenge to get the number of iterations and salt
         # XXX we don't support anything but sha prf
-        if prf.lower() <> 'sha':
+        if prf.lower() <> b'sha':
             return False
         try:
             iterations = int(iterations)
@@ -223,7 +227,7 @@ def make_secret(password, scheme=None):
     if not scheme_class:
         raise errors.BadPasswordSchemeError(scheme)
     secret = scheme_class.make_secret(password)
-    return '{%s}%s' % (scheme_class.TAG, secret)
+    return b'{{{0}}}{1}'.format(scheme_class.TAG, secret)
 
 
 def check_response(challenge, response):
diff --git a/mailman/pipeline/__init__.py b/mailman/pipeline/__init__.py
index d6e1b0129..f73061874 100644
--- a/mailman/pipeline/__init__.py
+++ b/mailman/pipeline/__init__.py
@@ -17,6 +17,8 @@
 
 """The built in set of pipeline handlers."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'initialize',
diff --git a/mailman/pipeline/acknowledge.py b/mailman/pipeline/acknowledge.py
index f1bd585f6..de520df65 100644
--- a/mailman/pipeline/acknowledge.py
+++ b/mailman/pipeline/acknowledge.py
@@ -20,8 +20,12 @@
 This only happens if the sender has set their AcknowledgePosts attribute.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
-__all__ = ['Acknowledge']
+__all__ = [
+    'Acknowledge',
+    ]
 
 
 from zope.interface import implements
diff --git a/mailman/pipeline/after_delivery.py b/mailman/pipeline/after_delivery.py
index d19d4a541..4626ba292 100644
--- a/mailman/pipeline/after_delivery.py
+++ b/mailman/pipeline/after_delivery.py
@@ -17,6 +17,8 @@
 
 """Perform some bookkeeping after a successful post."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'AfterDelivery',
diff --git a/mailman/pipeline/avoid_duplicates.py b/mailman/pipeline/avoid_duplicates.py
index 10c047004..0458e117c 100644
--- a/mailman/pipeline/avoid_duplicates.py
+++ b/mailman/pipeline/avoid_duplicates.py
@@ -23,8 +23,12 @@ has already received a copy, we either drop the message, add a duplicate
 warning header, or pass it through, depending on the user's preferences.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
-__all__ = ['AvoidDuplicates']
+__all__ = [
+    'AvoidDuplicates',
+    ]
 
 
 from email.Utils import getaddresses, formataddr
diff --git a/mailman/pipeline/calculate_recipients.py b/mailman/pipeline/calculate_recipients.py
index 9385c64e8..9837c1e6b 100644
--- a/mailman/pipeline/calculate_recipients.py
+++ b/mailman/pipeline/calculate_recipients.py
@@ -23,8 +23,12 @@ on the `recips' attribute of the message.  This attribute is used by the
 SendmailDeliver and BulkDeliver modules.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
-__all__ = ['CalculateRecipients']
+__all__ = [
+    'CalculateRecipients',
+    ]
 
 from zope.interface import implements
 
@@ -83,7 +87,7 @@ class CalculateRecipients:
 Your urgent message to the %(realname)s mailing list was not authorized for
 delivery.  The original message as received by Mailman is attached.
 """)
-                raise errors.RejectMessage, Utils.wrap(text)
+                raise errors.RejectMessage(Utils.wrap(text))
         # Calculate the regular recipients of the message
         recips = set(member.address.address
                      for member in mlist.regular_members.members
@@ -133,8 +137,8 @@ def do_topic_filters(mlist, msg, msgdata, recips):
                 # The user did not select any topics of interest, so he gets
                 # this message by default.
                 continue
-            if not mlist.getMemberOption(user,
-                                         config.ReceiveNonmatchingTopics):
+            if not mlist.getMemberOption(
+                user, config.ReceiveNonmatchingTopics):
                 # The user has interest in some topics, but elects not to
                 # receive message that match no topics, so zap him.
                 zaprecips.append(user)
diff --git a/mailman/pipeline/cleanse.py b/mailman/pipeline/cleanse.py
index 28c660bdc..330f415c2 100644
--- a/mailman/pipeline/cleanse.py
+++ b/mailman/pipeline/cleanse.py
@@ -17,8 +17,12 @@
 
 """Cleanse certain headers from all messages."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
-__all__ = ['Cleanse']
+__all__ = [
+    'Cleanse',
+    ]
 
 
 import logging
diff --git a/mailman/pipeline/cleanse_dkim.py b/mailman/pipeline/cleanse_dkim.py
index 774fa78cf..38623079c 100644
--- a/mailman/pipeline/cleanse_dkim.py
+++ b/mailman/pipeline/cleanse_dkim.py
@@ -25,6 +25,8 @@ and it will also give the MTA the opportunity to regenerate valid keys
 originating at the Mailman server for the outgoing message.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'CleanseDKIM',
diff --git a/mailman/pipeline/cook_headers.py b/mailman/pipeline/cook_headers.py
index 88051970e..529d7ce5d 100644
--- a/mailman/pipeline/cook_headers.py
+++ b/mailman/pipeline/cook_headers.py
@@ -17,6 +17,8 @@
 
 """Cook a message's headers."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'CookHeaders',
@@ -178,7 +180,7 @@ def process(mlist, msg, msgdata):
     if msgdata.get('_nolist') or not mlist.include_rfc2369_headers:
         return
     # This will act like an email address for purposes of formataddr()
-    listid = '%s.%s' % (mlist.list_name, mlist.host_name)
+    listid = '{0}.{1}'.format(mlist.list_name, mlist.host_name)
     cset = Utils.GetCharSet(mlist.preferred_language)
     if mlist.description:
         # Don't wrap the header since here we just want to get it properly RFC
@@ -187,7 +189,7 @@ def process(mlist, msg, msgdata):
         listid_h = formataddr((str(i18ndesc), listid))
     else:
         # without desc we need to ensure the MUST brackets
-        listid_h = '<%s>' % listid
+        listid_h = '<{0}>'.format(listid)
     # We always add a List-ID: header.
     del msg['list-id']
     msg['List-Id'] = listid_h
@@ -195,7 +197,7 @@ def process(mlist, msg, msgdata):
     # "X-List-Administrivia: yes" header.  For all others (i.e. those coming
     # from list posts), we add a bunch of other RFC 2369 headers.
     requestaddr = mlist.request_address
-    subfieldfmt = '<%s>, <mailto:%s>'
+    subfieldfmt = '<{0}>, <mailto:{1}>'
     listinfo = mlist.script_url('listinfo')
     headers = {}
     # XXX reduced_list_headers used to suppress List-Help, List-Subject, and
@@ -203,20 +205,21 @@ def process(mlist, msg, msgdata):
     # any more, so always add those three headers (others will still be
     # suppressed).
     headers.update({
-        'List-Help'       : '<mailto:%s?subject=help>' % requestaddr,
-        'List-Unsubscribe': subfieldfmt % (listinfo, mlist.leave_address),
-        'List-Subscribe'  : subfieldfmt % (listinfo, mlist.join_address),
+        'List-Help'       : '<mailto:{0}?subject=help>'.format(requestaddr),
+        'List-Unsubscribe': subfieldfmt.format(listinfo, mlist.leave_address),
+        'List-Subscribe'  : subfieldfmt.format(listinfo, mlist.join_address),
         })
     if msgdata.get('reduced_list_headers'):
         headers['X-List-Administrivia'] = 'yes'
     else:
         # List-Post: is controlled by a separate attribute
         if mlist.include_list_post_header:
-            headers['List-Post'] = '<mailto:%s>' % mlist.posting_address
+            headers['List-Post'] = '<mailto:{0}>'.format(mlist.posting_address)
         # Add RFC 2369 and 5064 archiving headers, if archiving is enabled.
         if mlist.archive:
             for archiver in config.archivers:
-                headers['List-Archive'] = '<%s>' % archiver.list_url(mlist)
+                headers['List-Archive'] = '<{0}>'.format(
+                    archiver.list_url(mlist))
                 permalink = archiver.permalink(mlist, msg)
                 if permalink is not None:
                     headers['Archived-At'] = permalink
@@ -333,7 +336,7 @@ def ch_oneline(headerstr):
             cset = 'utf-8'
         h = make_header(d)
         ustr = unicode(h)
-        oneline = u''.join(ustr.splitlines())
+        oneline = ''.join(ustr.splitlines())
         return oneline.encode(cset, 'replace'), cset
     except (LookupError, UnicodeError, ValueError, HeaderParseError):
         # possibly charset problem. return with undecoded string in one line.
diff --git a/mailman/pipeline/decorate.py b/mailman/pipeline/decorate.py
index bf9fbea80..82851fbf1 100644
--- a/mailman/pipeline/decorate.py
+++ b/mailman/pipeline/decorate.py
@@ -17,15 +17,18 @@
 
 """Decorate a message by sticking the header and footer around it."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
-__all__ = ['Decorate']
+__all__ = [
+    'Decorate',
+    ]
 
 
 import re
 import logging
 
 from email.MIMEText import MIMEText
-from string import Template
 from zope.interface import implements
 
 from mailman import Utils
@@ -33,6 +36,7 @@ from mailman.Message import Message
 from mailman.config import config
 from mailman.i18n import _
 from mailman.interfaces.handler import IHandler
+from mailman.utilities.string import expand
 
 
 log = logging.getLogger('mailman.error')
@@ -197,17 +201,18 @@ def decorate(mlist, template, extradict=None):
     # Create a dictionary which includes the default set of interpolation
     # variables allowed in headers and footers.  These will be augmented by
     # any key/value pairs in the extradict.
-    d = dict(real_name      = mlist.real_name,
-             list_name      = mlist.list_name,
-             fqdn_listname  = mlist.fqdn_listname,
-             host_name      = mlist.host_name,
-             listinfo_page  = mlist.script_url('listinfo'),
-             description    = mlist.description,
-             info           = mlist.info,
-             )
+    substitutions = dict(
+        real_name       = mlist.real_name,
+        list_name       = mlist.list_name,
+        fqdn_listname   = mlist.fqdn_listname,
+        host_name       = mlist.host_name,
+        listinfo_page   = mlist.script_url('listinfo'),
+        description     = mlist.description,
+        info            = mlist.info,
+        )
     if extradict is not None:
-        d.update(extradict)
-    text = Template(template).safe_substitute(d)
+        substitutions.update(extradict)
+    text = expand(template, substitutions)
     # Turn any \r\n line endings into just \n
     return re.sub(r' *\r?\n', r'\n', text)
 
diff --git a/mailman/pipeline/docs/archives.txt b/mailman/pipeline/docs/archives.txt
index d81f6e27b..d90228525 100644
--- a/mailman/pipeline/docs/archives.txt
+++ b/mailman/pipeline/docs/archives.txt
@@ -105,8 +105,9 @@ But if the value is 'yes', then the message will be archived.
     <BLANKLINE>
     A message of great import.
     <BLANKLINE>
-    >>> sorted(qdata.items())
-    [('_parsemsg', False), ('received_time', ...), ('version', 3)]
+    >>> dump_msgdata(qdata)
+    _parsemsg: False
+    version  : 3
 
 Without either archiving header, and all other things being the same, the
 message will get archived.
@@ -127,5 +128,6 @@ message will get archived.
     <BLANKLINE>
     A message of great import.
     <BLANKLINE>
-    >>> sorted(qdata.items())
-    [('_parsemsg', False), ('received_time', ...), ('version', 3)]
+    >>> dump_msgdata(qdata)
+    _parsemsg: False
+    version  : 3
diff --git a/mailman/pipeline/docs/digests.txt b/mailman/pipeline/docs/digests.txt
index e94f9912f..cb939f7ca 100644
--- a/mailman/pipeline/docs/digests.txt
+++ b/mailman/pipeline/docs/digests.txt
@@ -254,12 +254,14 @@ digest and an RFC 1153 plain text digest.  The size threshold is in KB.
     <BLANKLINE>
     --...
     --...
-    >>> sorted(mimedata.items())
-    [('_parsemsg', False),
-     ('isdigest', True),
-     ('listname', u'_xtest@example.com'),
-     ('received_time', ...),
-     ('recips', set([])), ('version', 3)]
+    >>> dump_msgdata(mimedata)
+    _parsemsg: False
+    isdigest : True
+    listname : _xtest@example.com
+    recips   : set([])
+    version  : 3
+
+
     >>> print rfc1153msg.as_string()
     From: _xtest-request@example.com
     Subject: XTest Digest, Vol 2, Issue 10
@@ -389,12 +391,12 @@ digest and an RFC 1153 plain text digest.  The size threshold is in KB.
     End of XTest Digest, Vol 2, Issue 10
     ************************************
     <BLANKLINE>
-    >>> sorted(rfc1153data.items())
-    [('_parsemsg', False),
-     ('isdigest', True),
-     ('listname', u'_xtest@example.com'),
-     ('received_time', ...),
-     ('recips', set([])), ('version', 3)]
+    >>> dump_msgdata(rfc1153data)
+    _parsemsg: False
+    isdigest : True
+    listname : _xtest@example.com
+    recips   : set([])
+    version  : 3
 
 
 Internationalized digests
@@ -505,12 +507,13 @@ Set the digest threshold to zero so that the digests will be sent immediately.
     <BLANKLINE>
     --...
     --...
-    >>> sorted(mimedata.items())
-    [('_parsemsg', False),
-     ('isdigest', True),
-     ('listname', u'_xtest@example.com'),
-     ('received_time', ...),
-     ('recips', set([])), ('version', 3)]
+    >>> dump_msgdata(mimedata)
+    _parsemsg: False
+    isdigest : True
+    listname : _xtest@example.com
+    recips   : set([])
+    version  : 3
+
     >>> print rfc1153msg.as_string()
     From: _xtest-request@example.com
     Subject: Groupe XTest, Vol. 2, Parution 11
@@ -524,15 +527,9 @@ Set the digest threshold to zero so that the digests will be sent immediately.
     <BLANKLINE>
     ...
     <BLANKLINE>
-    >>> sorted(rfc1153data.items())
-    [('_parsemsg', False),
-     ('isdigest', True),
-     ('listname', u'_xtest@example.com'),
-     ('received_time', ...),
-     ('recips', set([])), ('version', 3)]
-
-
-Clean up
---------
-
-    >>> config.DEFAULT_SERVER_LANGUAGE = u'en'
+    >>> dump_msgdata(rfc1153data)
+    _parsemsg: False
+    isdigest : True
+    listname : _xtest@example.com
+    recips   : set([])
+    version  : 3
diff --git a/mailman/pipeline/docs/nntp.txt b/mailman/pipeline/docs/nntp.txt
index 0120de394..3f48be1da 100644
--- a/mailman/pipeline/docs/nntp.txt
+++ b/mailman/pipeline/docs/nntp.txt
@@ -59,8 +59,7 @@ messages are gated to.
     <BLANKLINE>
     Something of great import.
     <BLANKLINE>
-    >>> sorted(msgdata.items())
-    [('_parsemsg', False),
-     ('listname', u'_xtest@example.com'),
-     ('received_time', ...),
-     ('version', 3)]
+    >>> dump_msgdata(msgdata)
+    _parsemsg: False
+    listname : _xtest@example.com
+    version  : 3
diff --git a/mailman/pipeline/docs/to-outgoing.txt b/mailman/pipeline/docs/to-outgoing.txt
index 6142d86c7..5305db19f 100644
--- a/mailman/pipeline/docs/to-outgoing.txt
+++ b/mailman/pipeline/docs/to-outgoing.txt
@@ -51,12 +51,13 @@ additional key set: the mailing list name.
     Subject: Here is a message
     <BLANKLINE>
     Something of great import.
-    >>> sorted(qmsgdata.items())    
-    [('_parsemsg', False),
-     ('bar', 2), ('foo', 1),
-     ('listname', u'_xtest@example.com'),
-     ('received_time', ...),
-     ('verp', True), ('version', 3)]
+    >>> dump_msgdata(qmsgdata)
+    _parsemsg: False
+    bar      : 2
+    foo      : 1
+    listname : _xtest@example.com
+    verp     : True
+    version  : 3
     >>> queue_size()
     0
 
diff --git a/mailman/pipeline/file_recipients.py b/mailman/pipeline/file_recipients.py
index f356e2e18..89d10d783 100644
--- a/mailman/pipeline/file_recipients.py
+++ b/mailman/pipeline/file_recipients.py
@@ -17,6 +17,8 @@
 
 """Get the normal delivery recipients from a Sendmail style :include: file."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'FileRecipients',
diff --git a/mailman/pipeline/mime_delete.py b/mailman/pipeline/mime_delete.py
index c7e27bd5f..3c4e4154f 100644
--- a/mailman/pipeline/mime_delete.py
+++ b/mailman/pipeline/mime_delete.py
@@ -24,8 +24,12 @@ wrapping only single sections after other processing are replaced by their
 contents.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
-__all__ = ['MIMEDelete']
+__all__ = [
+    'MIMEDelete',
+    ]
 
 
 import os
@@ -118,7 +122,7 @@ def process(mlist, msg, msgdata):
             reset_payload(msg, useful)
             changedp = 1
     if changedp:
-        msg['X-Content-Filtered-By'] = 'Mailman/MimeDel %s' % VERSION
+        msg['X-Content-Filtered-By'] = 'Mailman/MimeDel {0}'.format(VERSION)
 
 
 
@@ -146,7 +150,7 @@ def reset_payload(msg, subpart):
 def filter_parts(msg, filtertypes, passtypes, filterexts, passexts):
     # Look at all the message's subparts, and recursively filter
     if not msg.is_multipart():
-        return 1
+        return True
     payload = msg.get_payload()
     prelen = len(payload)
     newpayload = []
@@ -176,8 +180,8 @@ def filter_parts(msg, filtertypes, passtypes, filterexts, passexts):
     msg.set_payload(newpayload)
     if postlen == 0 and prelen > 0:
         # We threw away everything
-        return 0
-    return 1
+        return False
+    return True
 
 
 
@@ -199,12 +203,12 @@ def collapse_multipart_alternatives(msg):
 
 
 def to_plaintext(msg):
-    changedp = 0
+    changedp = False
     for subpart in typed_subpart_iterator(msg, 'text', 'html'):
         filename = tempfile.mktemp('.html')
         fp = open(filename, 'w')
         try:
-            fp.write(subpart.get_payload(decode=1))
+            fp.write(subpart.get_payload(decode=True))
             fp.close()
             cmd = os.popen(config.HTML_TO_PLAIN_TEXT_COMMAND %
                            {'filename': filename})
@@ -222,7 +226,7 @@ def to_plaintext(msg):
         del subpart['content-transfer-encoding']
         subpart.set_payload(plaintext)
         subpart.set_type('text/plain')
-        changedp = 1
+        changedp = True
     return changedp
 
 
@@ -251,6 +255,7 @@ are receiving the only remaining copy of the discarded message.
     # Most cases also discard the message
     raise errors.DiscardMessage
 
+
 def get_file_ext(m):
     """
     Get filename extension. Caution: some virus don't put filename
diff --git a/mailman/pipeline/moderate.py b/mailman/pipeline/moderate.py
index ec0a555d8..0b38c3a5a 100644
--- a/mailman/pipeline/moderate.py
+++ b/mailman/pipeline/moderate.py
@@ -17,6 +17,14 @@
 
 """Posting moderation filter."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'process',
+    ]
+
+
 import re
 
 from email.MIMEMessage import MIMEMessage
diff --git a/mailman/pipeline/owner_recipients.py b/mailman/pipeline/owner_recipients.py
index 046cac50c..ceb6ae0a1 100644
--- a/mailman/pipeline/owner_recipients.py
+++ b/mailman/pipeline/owner_recipients.py
@@ -17,11 +17,18 @@
 
 """Calculate the list owner recipients (includes moderators)."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'process',
+    ]
+
 
 
 def process(mlist, msg, msgdata):
     # The recipients are the owner and the moderator
     msgdata['recips'] = mlist.owner + mlist.moderator
     # Don't decorate these messages with the header/footers
-    msgdata['nodecorate'] = 1
-    msgdata['personalize'] = 0
+    msgdata['nodecorate'] = True
+    msgdata['personalize'] = False
diff --git a/mailman/pipeline/replybot.py b/mailman/pipeline/replybot.py
index ee0894d12..e24777774 100644
--- a/mailman/pipeline/replybot.py
+++ b/mailman/pipeline/replybot.py
@@ -17,21 +17,25 @@
 
 """Handler for auto-responses."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
-__all__ = ['Replybot']
+__all__ = [
+    'Replybot',
+    ]
 
 
 import time
 import logging
 import datetime
 
-from string import Template
 from zope.interface import implements
 
 from mailman import Message
 from mailman import Utils
 from mailman.i18n import _
 from mailman.interfaces.handler import IHandler
+from mailman.utilities.string import expand
 
 
 log = logging.getLogger('mailman.error')
@@ -97,7 +101,7 @@ def process(mlist, msg, msgdata):
     else:
         rtext = mlist.autoresponse_postings_text
     # Interpolation and Wrap the response text.
-    text = Utils.wrap(Template(rtext).safe_substitute(d))
+    text = Utils.wrap(expand(rtext, d))
     outmsg = Message.UserNotification(sender, mlist.bounces_address,
                                       subject, text, mlist.preferred_language)
     outmsg['X-Mailer'] = _('The Mailman Replybot')
diff --git a/mailman/pipeline/scrubber.py b/mailman/pipeline/scrubber.py
index f7ffd51e1..fa9c8577f 100644
--- a/mailman/pipeline/scrubber.py
+++ b/mailman/pipeline/scrubber.py
@@ -17,6 +17,8 @@
 
 """Cleanse a message for archiving."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Scrubber',
diff --git a/mailman/pipeline/tagger.py b/mailman/pipeline/tagger.py
index db4bb13b9..9a0acc1e3 100644
--- a/mailman/pipeline/tagger.py
+++ b/mailman/pipeline/tagger.py
@@ -17,8 +17,12 @@
 
 """Extract topics from the original mail message."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
-__all__ = ['Tagger']
+__all__ = [
+    'Tagger',
+    ]
 
 
 import re
@@ -35,7 +39,7 @@ from mailman.interfaces.handler import IHandler
 
 OR = '|'
 CRNL = '\r\n'
-EMPTYSTRING = ''
+EMPTYBYTES = b''
 NLTAB = '\n\t'
 
 
@@ -69,8 +73,10 @@ def process(mlist, msg, msgdata):
                 hits[name] = 1
                 break
     if hits:
-        msgdata['topichits'] = hits.keys()
-        msg['X-Topics'] = NLTAB.join(hits.keys())
+        # Sort the keys and make them available both in the message metadata
+        # and in a message header.
+        msgdata['topichits'] = sorted(hits)
+        msg['X-Topics'] = NLTAB.join(sorted(hits))
 
 
 
@@ -97,7 +103,7 @@ def scanbody(msg, numlines=None):
     reader = list(email.Iterators.body_line_iterator(msg))
     while numlines is None or lineno < numlines:
         try:
-            line = reader.pop(0)
+            line = bytes(reader.pop(0))
         except IndexError:
             break
         # Blank lines don't count
@@ -108,7 +114,7 @@ def scanbody(msg, numlines=None):
     # Concatenate those body text lines with newlines, and then create a new
     # message object from those lines.
     p = _ForgivingParser()
-    msg = p.parsestr(EMPTYSTRING.join(lines))
+    msg = p.parsestr(EMPTYBYTES.join(lines))
     return msg.get_all('subject', []) + msg.get_all('keywords', [])
 
 
diff --git a/mailman/pipeline/to_archive.py b/mailman/pipeline/to_archive.py
index 15f4c856e..7f1702fe9 100644
--- a/mailman/pipeline/to_archive.py
+++ b/mailman/pipeline/to_archive.py
@@ -17,6 +17,8 @@
 
 """Add the message to the archives."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'ToArchive',
diff --git a/mailman/pipeline/to_digest.py b/mailman/pipeline/to_digest.py
index e56c4a109..df2684986 100644
--- a/mailman/pipeline/to_digest.py
+++ b/mailman/pipeline/to_digest.py
@@ -25,6 +25,8 @@
 # directory and the DigestRunner will craft the MIME, rfc1153, and
 # (eventually) URL-subject linked digests from the mbox.
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'ToDigest',
@@ -243,9 +245,9 @@ def send_i18n_digests(mlist, mboxfp):
             if not username:
                 username = addresses[0][1]
         if username:
-            username = ' (%s)' % username
+            username = ' ({0})'.format(username)
         # Put count and Wrap the toc subject line
-        wrapped = Utils.wrap('%2d. %s' % (msgcount, subject), 65)
+        wrapped = Utils.wrap('{0:2}. {1}'.format(msgcount, subject), 65)
         slines = wrapped.split('\n')
         # See if the user's name can fit on the last line
         if len(slines[-1]) + len(username) > 70:
@@ -326,8 +328,8 @@ def send_i18n_digests(mlist, mboxfp):
         # Honor the default setting
         for h in config.digests.plain_digest_keep_headers.split():
             if msg[h]:
-                uh = Utils.wrap('%s: %s' % (h, Utils.oneline(msg[h],
-                                                             in_unicode=True)))
+                uh = Utils.wrap('{0}: {1}'.format(
+                    h, Utils.oneline(msg[h], in_unicode=True)))
                 uh = '\n\t'.join(uh.split('\n'))
                 print >> plainmsg, uh
         print >> plainmsg
@@ -402,8 +404,8 @@ def send_i18n_digests(mlist, mboxfp):
             mimerecips.add(email_address)
         else:
             raise AssertionError(
-                'Digest member "%s" unexpected delivery mode: %s' %
-                (email_address, member.delivery_mode))
+                'Digest member "{0}" unexpected delivery mode: {1}'.format(
+                    email_address, member.delivery_mode))
     # Zap this since we're now delivering the last digest to these folks.
     mlist.one_last_digest.clear()
     # MIME
diff --git a/mailman/pipeline/to_outgoing.py b/mailman/pipeline/to_outgoing.py
index 9ff7ab88a..ff27593c4 100644
--- a/mailman/pipeline/to_outgoing.py
+++ b/mailman/pipeline/to_outgoing.py
@@ -22,6 +22,8 @@ posted to the list membership.  Anything else that needs to go out to some
 recipient should just be placed in the out queue directly.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'ToOutgoing',
diff --git a/mailman/pipeline/to_usenet.py b/mailman/pipeline/to_usenet.py
index a635b65b3..220374348 100644
--- a/mailman/pipeline/to_usenet.py
+++ b/mailman/pipeline/to_usenet.py
@@ -17,8 +17,12 @@
 
 """Move the message to the mail->news queue."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
-__all__ = ['ToUsenet']
+__all__ = [
+    'ToUsenet',
+    ]
 
 
 import logging
diff --git a/mailman/queue/__init__.py b/mailman/queue/__init__.py
index e6d39ee1b..cb2225b13 100644
--- a/mailman/queue/__init__.py
+++ b/mailman/queue/__init__.py
@@ -24,6 +24,8 @@ written.  First, the message is written to the pickle, then the metadata
 dictionary is written.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Runner',
@@ -45,7 +47,6 @@ import traceback
 
 from cStringIO import StringIO
 from lazr.config import as_boolean, as_timedelta
-from string import Template
 from zope.interface import implements
 
 from mailman import Message
@@ -54,6 +55,7 @@ from mailman import i18n
 from mailman.config import config
 from mailman.interfaces.runner import IRunner
 from mailman.interfaces.switchboard import ISwitchboard
+from mailman.utilities.string import expand
 
 # 20 bytes of all bits set, maximum hashlib.sha.digest() value
 shamax = 0xffffffffffffffffffffffffffffffffffffffffL
@@ -81,10 +83,10 @@ class Switchboard:
         for conf in config.qrunner_configs:
             name = conf.name.split('.')[-1]
             assert name not in config.switchboards, (
-                'Duplicate qrunner name: %s' % name)
+                'Duplicate qrunner name: {0}'.format(name))
             substitutions = config.paths
             substitutions['name'] = name
-            path = Template(conf.path).safe_substitute(substitutions)
+            path = expand(conf.path, substitutions)
             config.switchboards[name] = Switchboard(path)
 
     def __init__(self, queue_directory,
@@ -103,7 +105,7 @@ class Switchboard:
         :type recover: bool
         """
         assert (numslices & (numslices - 1)) == 0, (
-            'Not a power of 2: %s' % numslices)
+            'Not a power of 2: {0}'.format(numslices))
         self.queue_directory = queue_directory
         # Create the directory if it doesn't yet exist.
         Utils.makedirs(self.queue_directory, 0770)
@@ -148,7 +150,8 @@ class Switchboard:
         tmpfile = filename + '.tmp'
         # Always add the metadata schema version number
         data['version'] = config.QFILE_SCHEMA_VERSION
-        # Filter out volatile entries
+        # Filter out volatile entries.  Use .keys() so that we can mutate the
+        # dictionary during the iteration.
         for k in data.keys():
             if k.startswith('_'):
                 del data[k]
@@ -197,7 +200,7 @@ class Switchboard:
                 os.rename(bakfile, psvfile)
             else:
                 os.unlink(bakfile)
-        except EnvironmentError, e:
+        except EnvironmentError:
             elog.exception(
                 'Failed to unlink/preserve backup file: %s', bakfile)
 
@@ -246,11 +249,11 @@ class Switchboard:
                     msg = cPickle.load(fp)
                     data_pos = fp.tell()
                     data = cPickle.load(fp)
-                except Exception, s:
+                except Exception as error:
                     # If unpickling throws any exception, just log and
                     # preserve this entry
                     elog.error('Unpickling .bak exception: %s\n'
-                               'Preserving file: %s', s, filebase)
+                               'Preserving file: %s', error, filebase)
                     self.finish(filebase, preserve=True)
                 else:
                     data['_bak_count'] = data.get('_bak_count', 0) + 1
@@ -289,8 +292,7 @@ class Runner:
         section = getattr(config, 'qrunner.' + name)
         substitutions = config.paths
         substitutions['name'] = name
-        self.queue_directory = Template(section.path).safe_substitute(
-            substitutions)
+        self.queue_directory = expand(section.path, substitutions)
         numslices = int(section.instances)
         self.switchboard = Switchboard(
             self.queue_directory, slice, numslices, True)
@@ -304,7 +306,7 @@ class Runner:
         self._stop = False
 
     def __repr__(self):
-        return '<%s at %s>' % (self.__class__.__name__, id(self))
+        return '<{0} at {1:#x}>'.format(self.__class__.__name__, id(self))
 
     def stop(self):
         """See `IRunner`."""
@@ -345,13 +347,13 @@ class Runner:
                 # Ask the switchboard for the message and metadata objects
                 # associated with this queue file.
                 msg, msgdata = self.switchboard.dequeue(filebase)
-            except Exception, e:
+            except Exception as error:
                 # This used to just catch email.Errors.MessageParseError, but
                 # other problems can occur in message parsing, e.g.
                 # ValueError, and exceptions can occur in unpickling too.  We
                 # don't want the runner to die, so we just log and skip this
                 # entry, but preserve it for analysis.
-                self._log(e)
+                self._log(error)
                 elog.error('Skipping and preserving unparseable message: %s',
                            filebase)
                 self.switchboard.finish(filebase, preserve=True)
@@ -362,14 +364,14 @@ class Runner:
                 self._process_one_file(msg, msgdata)
                 dlog.debug('[%s] finishing filebase: %s', me, filebase)
                 self.switchboard.finish(filebase)
-            except Exception, e:
+            except Exception as error:
                 # All runners that implement _dispose() must guarantee that
                 # exceptions are caught and dealt with properly.  Still, there
                 # may be a bug in the infrastructure, and we do not want those
                 # to cause messages to be lost.  Any uncaught exceptions will
                 # cause the message to be stored in the shunt queue for human
                 # intervention.
-                self._log(e)
+                self._log(error)
                 # Put a marker in the metadata for unshunting.
                 msgdata['whichq'] = self.switchboard.queue_directory
                 # It is possible that shunting can throw an exception, e.g. a
@@ -380,11 +382,11 @@ class Runner:
                     new_filebase = shunt.enqueue(msg, msgdata)
                     elog.error('SHUNTING: %s', new_filebase)
                     self.switchboard.finish(filebase)
-                except Exception, e:
+                except Exception as error:
                     # The message wasn't successfully shunted.  Log the
                     # exception and try to preserve the original queue entry
                     # for possible analysis.
-                    self._log(e)
+                    self._log(error)
                     elog.error(
                         'SHUNTING FAILED, preserving original entry: %s',
                         filebase)
diff --git a/mailman/queue/docs/runner.txt b/mailman/queue/docs/runner.txt
index db493110c..d24a8334c 100644
--- a/mailman/queue/docs/runner.txt
+++ b/mailman/queue/docs/runner.txt
@@ -61,10 +61,12 @@ on instance variables.
     <BLANKLINE>
     A test message.
     <BLANKLINE>
-    >>> sorted(runner.msgdata.items())
-    [('_parsemsg', False),
-     ('bar', 'no'), ('foo', 'yes'),
-     ('lang', u'en'), ('listname', u'_xtest@example.com'),
-     ('received_time', ...), ('version', 3)]
+    >>> dump_msgdata(runner.msgdata)
+    _parsemsg: False
+    bar      : no
+    foo      : yes
+    lang     : en
+    listname : _xtest@example.com
+    version  : 3
 
 XXX More of the Runner API should be tested.
diff --git a/mailman/queue/docs/switchboard.txt b/mailman/queue/docs/switchboard.txt
index 741d435e1..88ab6ea93 100644
--- a/mailman/queue/docs/switchboard.txt
+++ b/mailman/queue/docs/switchboard.txt
@@ -29,7 +29,10 @@ Here's a helper function for ensuring things work correctly.
     ...     for qfile in os.listdir(directory):
     ...         root, ext = os.path.splitext(qfile)
     ...         files[ext] = files.get(ext, 0) + 1
-    ...     return sorted(files.items())
+    ...     if len(files) == 0:
+    ...         print 'empty'
+    ...     for ext in sorted(files):
+    ...         print '{0}: {1}'.format(ext, files[ext])
 
 
 Enqueing and dequeing
@@ -40,7 +43,7 @@ dictionary.
 
     >>> filebase = switchboard.enqueue(msg)
     >>> check_qfiles()
-    [('.pck', 1)]
+    .pck: 1
 
 To read the contents of a queue file, dequeue it.
 
@@ -51,17 +54,18 @@ To read the contents of a queue file, dequeue it.
     <BLANKLINE>
     A test message.
     <BLANKLINE>
-    >>> sorted(msgdata.items())
-    [('_parsemsg', False), ('received_time', ...), ('version', 3)]
+    >>> dump_msgdata(msgdata)
+    _parsemsg: False
+    version  : 3
     >>> check_qfiles()
-    [('.bak', 1)]
+    .bak: 1
 
 To complete the dequeing process, removing all traces of the message file,
 finish it (without preservation).
 
     >>> switchboard.finish(filebase)
     >>> check_qfiles()
-    []
+    empty
 
 When enqueing a file, you can provide additional metadata keys by using
 keyword arguments.
@@ -69,20 +73,21 @@ keyword arguments.
     >>> filebase = switchboard.enqueue(msg, {'foo': 1}, bar=2)
     >>> msg, msgdata = switchboard.dequeue(filebase)
     >>> switchboard.finish(filebase)
-    >>> sorted(msgdata.items())
-    [('_parsemsg', False),
-     ('bar', 2), ('foo', 1),
-     ('received_time', ...), ('version', 3)]
+    >>> dump_msgdata(msgdata)
+    _parsemsg: False
+    bar      : 2
+    foo      : 1
+    version  : 3
 
 Keyword arguments override keys from the metadata dictionary.
 
     >>> filebase = switchboard.enqueue(msg, {'foo': 1}, foo=2)
     >>> msg, msgdata = switchboard.dequeue(filebase)
     >>> switchboard.finish(filebase)
-    >>> sorted(msgdata.items())
-    [('_parsemsg', False),
-     ('foo', 2),
-     ('received_time', ...), ('version', 3)]
+    >>> dump_msgdata(msgdata)
+    _parsemsg: False
+    foo      : 2
+    version  : 3
 
 
 Iterating over files
@@ -99,7 +104,7 @@ iterate over just these files is to use the .files attribute.
     >>> sorted(switchboard.files) == filebases
     True
     >>> check_qfiles()
-    [('.pck', 3)]
+    .pck: 3
 
 You can also use the .get_files() method if you want to iterate over all the
 file bases for some other extension.
@@ -110,11 +115,11 @@ file bases for some other extension.
     >>> bakfiles == filebases
     True
     >>> check_qfiles()
-    [('.bak', 3)]
+    .bak: 3
     >>> for filebase in switchboard.get_files('.bak'):
     ...     switchboard.finish(filebase)
     >>> check_qfiles()
-    []
+    empty
 
 
 Recovering files
@@ -130,10 +135,10 @@ place.  These can be recovered when the switchboard is instantiated.
     ...     msg, msgdata = switchboard.dequeue(filebase)
     ...     # Don't call .finish()
     >>> check_qfiles()
-    [('.bak', 3)]
+    .bak: 3
     >>> switchboard_2 = Switchboard(queue_directory, recover=True)
     >>> check_qfiles()
-    [('.pck', 3)]
+    .pck: 3
 
 The files can be recovered explicitly.
 
@@ -141,10 +146,10 @@ The files can be recovered explicitly.
     ...     msg, msgdata = switchboard.dequeue(filebase)
     ...     # Don't call .finish()
     >>> check_qfiles()
-    [('.bak', 3)]
+    .bak: 3
     >>> switchboard.recover_backup_files()
     >>> check_qfiles()
-    [('.pck', 3)]
+    .pck: 3
 
 But the files will only be recovered at most three times before they are
 considered defective.  In order to prevent mail bombs and loops, once this
@@ -154,21 +159,21 @@ maximum is reached, the files will be preserved in the 'bad' queue.
     ...     msg, msgdata = switchboard.dequeue(filebase)
     ...     # Don't call .finish()
     >>> check_qfiles()
-    [('.bak', 3)]
+    .bak: 3
     >>> switchboard.recover_backup_files()
     >>> check_qfiles()
-    []
+    empty
 
     >>> bad = config.switchboards['bad']
     >>> check_qfiles(bad.queue_directory)
-    [('.psv', 3)]
+    .psv: 3
 
 Clean up
 
     >>> for file in os.listdir(bad.queue_directory):
     ...     os.remove(os.path.join(bad.queue_directory, file))
     >>> check_qfiles(bad.queue_directory)
-    []
+    empty
 
 
 Queue slices
diff --git a/mailman/rules/__init__.py b/mailman/rules/__init__.py
index 82a463f76..6c7034772 100644
--- a/mailman/rules/__init__.py
+++ b/mailman/rules/__init__.py
@@ -17,6 +17,8 @@
 
 """The built in rule set."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'initialize',
diff --git a/mailman/rules/administrivia.py b/mailman/rules/administrivia.py
index f21db6744..8807ef952 100644
--- a/mailman/rules/administrivia.py
+++ b/mailman/rules/administrivia.py
@@ -17,6 +17,8 @@
 
 """The administrivia rule."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Administrivia',
diff --git a/mailman/rules/any.py b/mailman/rules/any.py
index 71df37584..c337df7f1 100644
--- a/mailman/rules/any.py
+++ b/mailman/rules/any.py
@@ -17,8 +17,12 @@
 
 """Check if any previous rules have matched."""
 
-__all__ = ['Any']
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
+__all__ = [
+    'Any',
+    ]
 
 
 from zope.interface import implements
diff --git a/mailman/rules/approved.py b/mailman/rules/approved.py
index 79dc0d934..f81c1ad04 100644
--- a/mailman/rules/approved.py
+++ b/mailman/rules/approved.py
@@ -17,6 +17,8 @@
 
 """Look for moderator pre-approval."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'Approved',
@@ -31,7 +33,7 @@ from mailman.i18n import _
 from mailman.interfaces.rules import IRule
 
 
-EMPTYSTRING = u''
+EMPTYSTRING = ''
 
 
 
diff --git a/mailman/rules/docs/administrivia.txt b/mailman/rules/docs/administrivia.txt
index df6685074..dba882775 100644
--- a/mailman/rules/docs/administrivia.txt
+++ b/mailman/rules/docs/administrivia.txt
@@ -9,8 +9,8 @@ used to catch messages posted to the list which should have been sent to the
     >>> mlist = config.db.list_manager.create(u'_xtest@example.com')
     >>> mlist.administrivia = True
     >>> rule = config.rules['administrivia']
-    >>> rule.name
-    'administrivia'
+    >>> print rule.name
+    administrivia
 
 For example, if the Subject header contains the word 'unsubscribe', the rule
 matches.
diff --git a/mailman/rules/docs/approve.txt b/mailman/rules/docs/approve.txt
index cb3093e0d..dda531a4c 100644
--- a/mailman/rules/docs/approve.txt
+++ b/mailman/rules/docs/approve.txt
@@ -20,8 +20,8 @@ The 'approved' rule determines whether the message contains the proper
 approval or not.
 
     >>> rule = config.rules['approved']
-    >>> rule.name
-    'approved'
+    >>> print rule.name
+    approved
 
 
 No approval
diff --git a/mailman/rules/docs/implicit-dest.txt b/mailman/rules/docs/implicit-dest.txt
index 30db86611..e5c340dcd 100644
--- a/mailman/rules/docs/implicit-dest.txt
+++ b/mailman/rules/docs/implicit-dest.txt
@@ -6,8 +6,8 @@ not explicitly mentioned in the set of message recipients.
 
     >>> mlist = config.db.list_manager.create(u'_xtest@example.com')
     >>> rule = config.rules['implicit-dest']
-    >>> rule.name
-    'implicit-dest'
+    >>> print rule.name
+    implicit-dest
 
 This rule matches messages that have implicit destination, meaning that the
 mailing list's posting address isn't included in the explicit recipients.
diff --git a/mailman/rules/docs/loop.txt b/mailman/rules/docs/loop.txt
index 6391864b2..61612cd75 100644
--- a/mailman/rules/docs/loop.txt
+++ b/mailman/rules/docs/loop.txt
@@ -6,8 +6,8 @@ X-BeenThere header with the value of the list's posting address.
 
     >>> mlist = config.db.list_manager.create(u'_xtest@example.com')
     >>> rule = config.rules['loop']
-    >>> rule.name
-    'loop'
+    >>> print rule.name
+    loop
 
 The header could be missing, in which case the rule does not match.
 
diff --git a/mailman/rules/docs/max-size.txt b/mailman/rules/docs/max-size.txt
index ae7921f9c..117691e59 100644
--- a/mailman/rules/docs/max-size.txt
+++ b/mailman/rules/docs/max-size.txt
@@ -8,8 +8,8 @@ bytes).
 
     >>> mlist = config.db.list_manager.create(u'_xtest@example.com')
     >>> rule = config.rules['max-size']
-    >>> rule.name
-    'max-size'
+    >>> print rule.name
+    max-size
 
 For example, setting the maximum message size to 1 means that any message
 bigger than that will match the rule.
diff --git a/mailman/rules/docs/moderation.txt b/mailman/rules/docs/moderation.txt
index 5e002a850..65be0d7da 100644
--- a/mailman/rules/docs/moderation.txt
+++ b/mailman/rules/docs/moderation.txt
@@ -8,8 +8,8 @@ email the list without having those messages be held for approval.  The
 
     >>> mlist = config.db.list_manager.create(u'_xtest@example.com')
     >>> rule = config.rules['moderation']
-    >>> rule.name
-    'moderation'
+    >>> print rule.name
+    moderation
 
 In the simplest case, the sender is not a member of the mailing list, so the
 moderation rule can't match.
@@ -49,8 +49,8 @@ There is another, related rule for matching non-members, which simply matches
 if the sender is /not/ a member of the mailing list.
 
     >>> rule = config.rules['non-member']
-    >>> rule.name
-    'non-member'
+    >>> print rule.name
+    non-member
 
 If the sender is a member of this mailing list, the rule does not match.
 
diff --git a/mailman/rules/docs/news-moderation.txt b/mailman/rules/docs/news-moderation.txt
index 36310797c..4c095cc81 100644
--- a/mailman/rules/docs/news-moderation.txt
+++ b/mailman/rules/docs/news-moderation.txt
@@ -10,8 +10,8 @@ directly to the mailing list.
 
     >>> mlist = config.db.list_manager.create(u'_xtest@example.com')
     >>> rule = config.rules['news-moderation']
-    >>> rule.name
-    'news-moderation'
+    >>> print rule.name
+    news-moderation
 
 Set the list configuraiton variable to enable newsgroup moderation.
 
diff --git a/mailman/rules/docs/no-subject.txt b/mailman/rules/docs/no-subject.txt
index 4fa001308..576111cd7 100644
--- a/mailman/rules/docs/no-subject.txt
+++ b/mailman/rules/docs/no-subject.txt
@@ -6,8 +6,8 @@ the empty string when stripped.
 
     >>> mlist = config.db.list_manager.create(u'_xtest@example.com')
     >>> rule = config.rules['no-subject']
-    >>> rule.name
-    'no-subject'
+    >>> print rule.name
+    no-subject
 
 A message with a non-empty subject does not match the rule.
 
diff --git a/mailman/rules/docs/recipients.txt b/mailman/rules/docs/recipients.txt
index b364dd031..3cd49d501 100644
--- a/mailman/rules/docs/recipients.txt
+++ b/mailman/rules/docs/recipients.txt
@@ -6,8 +6,8 @@ number of explicit recipients addressed by the message.
 
     >>> mlist = config.db.list_manager.create(u'_xtest@example.com')
     >>> rule = config.rules['max-recipients']
-    >>> rule.name
-    'max-recipients'
+    >>> print rule.name
+    max-recipients
 
 In this case, we'll create a message with 5 recipients.  These include all
 addresses in the To and CC headers.
diff --git a/mailman/rules/docs/rules.txt b/mailman/rules/docs/rules.txt
index 1fba63b64..095d11466 100644
--- a/mailman/rules/docs/rules.txt
+++ b/mailman/rules/docs/rules.txt
@@ -57,8 +57,8 @@ For example, the emergency rule just checks to see if the emergency flag is
 set on the mailing list, and the message has not been pre-approved by the list
 administrator.
 
-    >>> rule.name
-    'emergency'
+    >>> print rule.name
+    emergency
     >>> mlist.emergency = False
     >>> rule.check(mlist, msg, {})
     False
diff --git a/mailman/rules/docs/suspicious.txt b/mailman/rules/docs/suspicious.txt
index 0cc515ae4..190a34aca 100644
--- a/mailman/rules/docs/suspicious.txt
+++ b/mailman/rules/docs/suspicious.txt
@@ -7,8 +7,8 @@ confusing to users, and the list attribute that controls this is misnamed.
 
     >>> mlist = config.db.list_manager.create(u'_xtest@example.com')
     >>> rule = config.rules['suspicious-header']
-    >>> rule.name
-    'suspicious-header'
+    >>> print rule.name
+    suspicious-header
 
 Set the so-called suspicious header configuration variable.
 
diff --git a/mailman/rules/emergency.py b/mailman/rules/emergency.py
index f24acba8c..c2cee06c4 100644
--- a/mailman/rules/emergency.py
+++ b/mailman/rules/emergency.py
@@ -17,8 +17,12 @@
 
 """The emergency hold rule."""
 
-__all__ = ['Emergency']
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
+__all__ = [
+    'Emergency',
+    ]
 
 
 from zope.interface import implements
@@ -33,10 +37,12 @@ class Emergency:
     implements(IRule)
 
     name = 'emergency'
+
     description = _(
         """The mailing list is in emergency hold and this message was not
         pre-approved by the list administrator.
         """)
+
     record = True
 
     def check(self, mlist, msg, msgdata):
diff --git a/mailman/rules/implicit_dest.py b/mailman/rules/implicit_dest.py
index 9320a9ea1..3ddffa2cf 100644
--- a/mailman/rules/implicit_dest.py
+++ b/mailman/rules/implicit_dest.py
@@ -17,8 +17,12 @@
 
 """The implicit destination rule."""
 
-__all__ = ['ImplicitDestination']
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
+__all__ = [
+    'ImplicitDestination',
+    ]
 
 
 import re
diff --git a/mailman/rules/loop.py b/mailman/rules/loop.py
index a0abbbaa4..564d20dc6 100644
--- a/mailman/rules/loop.py
+++ b/mailman/rules/loop.py
@@ -17,8 +17,12 @@
 
 """Look for a posting loop."""
 
-__all__ = ['Loop']
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
+__all__ = [
+    'Loop',
+    ]
 
 
 from zope.interface import implements
@@ -33,7 +37,7 @@ class Loop:
     implements(IRule)
 
     name = 'loop'
-    description = _("""Look for a posting loop, via the X-BeenThere header.""")
+    description = _('Look for a posting loop, via the X-BeenThere header.')
     record = True
 
     def check(self, mlist, msg, msgdata):
diff --git a/mailman/rules/max_recipients.py b/mailman/rules/max_recipients.py
index 6fa3e1ee4..a9cfd4a7f 100644
--- a/mailman/rules/max_recipients.py
+++ b/mailman/rules/max_recipients.py
@@ -17,8 +17,12 @@
 
 """The maximum number of recipients rule."""
 
-__all__ = ['MaximumRecipients']
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
+__all__ = [
+    'MaximumRecipients',
+    ]
 
 
 from email.utils import getaddresses
diff --git a/mailman/rules/max_size.py b/mailman/rules/max_size.py
index 1ce280e88..bac79bbab 100644
--- a/mailman/rules/max_size.py
+++ b/mailman/rules/max_size.py
@@ -17,8 +17,12 @@
 
 """The maximum message size rule."""
 
-__all__ = ['MaximumSize']
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
+__all__ = [
+    'MaximumSize',
+    ]
 
 
 from zope.interface import implements
diff --git a/mailman/rules/moderation.py b/mailman/rules/moderation.py
index 6f6bcfb36..708983f6b 100644
--- a/mailman/rules/moderation.py
+++ b/mailman/rules/moderation.py
@@ -17,11 +17,13 @@
 
 """Membership related rules."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
 __all__ = [
     'Moderation',
     'NonMember',
     ]
-__metaclass__ = type
 
 
 from zope.interface import implements
diff --git a/mailman/rules/news_moderation.py b/mailman/rules/news_moderation.py
index 822e43445..3ead80086 100644
--- a/mailman/rules/news_moderation.py
+++ b/mailman/rules/news_moderation.py
@@ -17,8 +17,12 @@
 
 """The news moderation rule."""
 
-__all__ = ['ModeratedNewsgroup']
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
+__all__ = [
+    'ModeratedNewsgroup',
+    ]
 
 
 from zope.interface import implements
@@ -35,7 +39,7 @@ class ModeratedNewsgroup:
 
     name = 'news-moderation'
     description = _(
-        u"""Match all messages posted to a mailing list that gateways to a
+        """Match all messages posted to a mailing list that gateways to a
         moderated newsgroup.
         """)
     record = True
diff --git a/mailman/rules/no_subject.py b/mailman/rules/no_subject.py
index 08848154d..2487867e7 100644
--- a/mailman/rules/no_subject.py
+++ b/mailman/rules/no_subject.py
@@ -17,8 +17,12 @@
 
 """The no-Subject header rule."""
 
-__all__ = ['NoSubject']
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
+__all__ = [
+    'NoSubject',
+    ]
 
 
 from zope.interface import implements
diff --git a/mailman/rules/suspicious.py b/mailman/rules/suspicious.py
index 019e6c09b..00e9a5e9e 100644
--- a/mailman/rules/suspicious.py
+++ b/mailman/rules/suspicious.py
@@ -17,6 +17,8 @@
 
 """The historical 'suspicious header' rule."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'SuspiciousHeader',
@@ -72,12 +74,12 @@ def _parse_matching_header_opt(mlist):
             value = line[i+1:].lstrip()
             try:
                 cre = re.compile(value, re.IGNORECASE)
-            except re.error, e:
+            except re.error as error:
                 # The regexp was malformed.  BAW: should do a better
                 # job of informing the list admin.
                 log.error("""\
 bad regexp in bounce_matching_header line: %s
-\n%s (cause: %s)""", mlist.real_name, value, e)
+\n%s (cause: %s)""", mlist.real_name, value, error)
             else:
                 all.append((header, cre, line))
     return all
diff --git a/mailman/rules/truth.py b/mailman/rules/truth.py
index 4d1a3cca7..45b5560c2 100644
--- a/mailman/rules/truth.py
+++ b/mailman/rules/truth.py
@@ -17,8 +17,12 @@
 
 """A rule which always matches."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
-__all__ = ['Truth']
+__all__ = [
+    'Truth',
+    ]
 
 
 from zope.interface import implements
diff --git a/mailman/styles/default.py b/mailman/styles/default.py
index 76b697296..d60773f51 100644
--- a/mailman/styles/default.py
+++ b/mailman/styles/default.py
@@ -17,6 +17,8 @@
 
 """Application of list styles to new and existing lists."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'DefaultStyle',
@@ -59,16 +61,16 @@ class DefaultStyle:
         mlist.max_num_recipients = 10
         mlist.max_message_size = 40 # KB
         mlist.reply_goes_to_list = ReplyToMunging.no_munging
-        mlist.reply_to_address = u''
+        mlist.reply_to_address = ''
         mlist.first_strip_reply_to = False
         mlist.admin_immed_notify = True
         mlist.admin_notify_mchanges = False
         mlist.require_explicit_destination = True
-        mlist.acceptable_aliases = u''
+        mlist.acceptable_aliases = ''
         mlist.send_reminders = True
         mlist.send_welcome_msg = True
         mlist.send_goodbye_msg = True
-        mlist.bounce_matching_headers = u"""
+        mlist.bounce_matching_headers = """
 # Lines that *start* with a '#' are comments.
 to: friend@public.com
 message-id: relay.comanche.denmark.eu
@@ -77,10 +79,10 @@ from: .*@uplinkpro.com
 """
         mlist.header_matches = []
         mlist.anonymous_list = False
-        mlist.description = u''
-        mlist.info = u''
-        mlist.welcome_msg = u''
-        mlist.goodbye_msg = u''
+        mlist.description = ''
+        mlist.info = ''
+        mlist.welcome_msg = ''
+        mlist.goodbye_msg = ''
         mlist.subscribe_policy = 1
         mlist.subscribe_auto_approval = []
         mlist.unsubscribe_policy = 0
@@ -111,8 +113,8 @@ from: .*@uplinkpro.com
         mlist.mime_is_default_digest = False
         mlist.digest_size_threshold = 30 # KB
         mlist.digest_send_periodic = True
-        mlist.digest_header = u''
-        mlist.digest_footer = u"""\
+        mlist.digest_header = ''
+        mlist.digest_footer = """\
 _______________________________________________
 $real_name mailing list
 $fqdn_listname
@@ -131,14 +133,14 @@ ${listinfo_page}
         mlist.archive_volume_frequency = 1
         mlist.emergency = False
         mlist.member_moderation_action = Action.hold
-        mlist.member_moderation_notice = u''
+        mlist.member_moderation_notice = ''
         mlist.accept_these_nonmembers = []
         mlist.hold_these_nonmembers = []
         mlist.reject_these_nonmembers = []
         mlist.discard_these_nonmembers = []
         mlist.forward_auto_discards = True
         mlist.generic_nonmember_action = 1
-        mlist.nonmember_rejection_notice = u''
+        mlist.nonmember_rejection_notice = ''
         # Ban lists
         mlist.ban_list = []
         # Max autoresponses per day.  A mapping between addresses and a
@@ -146,8 +148,8 @@ ${listinfo_page}
         # autoresponses sent on that date.
         mlist.hold_and_cmd_autoresponses = {}
         mlist.subject_prefix = _(u'[$mlist.real_name] ')
-        mlist.msg_header = u''
-        mlist.msg_footer = u"""\
+        mlist.msg_header = ''
+        mlist.msg_footer = """\
 _______________________________________________
 $real_name mailing list
 $fqdn_listname
@@ -171,9 +173,9 @@ ${listinfo_page}
         #  1 - autorespond, but discard the original message
         #  2 - autorespond, and forward the message on to be processed
         mlist.autorespond_requests = 0
-        mlist.autoresponse_postings_text = u''
-        mlist.autoresponse_admin_text = u''
-        mlist.autoresponse_request_text = u''
+        mlist.autoresponse_postings_text = ''
+        mlist.autoresponse_admin_text = ''
+        mlist.autoresponse_request_text = ''
         mlist.autoresponse_graceperiod = datetime.timedelta(days=90)
         mlist.postings_responses = {}
         mlist.admin_responses = {}
@@ -196,8 +198,8 @@ ${listinfo_page}
         # New style delivery status
         mlist.delivery_status = {}
         # NNTP gateway
-        mlist.nntp_host = u''
-        mlist.linked_newsgroup = u''
+        mlist.nntp_host = ''
+        mlist.linked_newsgroup = ''
         mlist.gateway_to_news = False
         mlist.gateway_to_mail = False
         mlist.news_prefix_subject_too = True
diff --git a/mailman/styles/manager.py b/mailman/styles/manager.py
index 0b84f20e0..cf3d07711 100644
--- a/mailman/styles/manager.py
+++ b/mailman/styles/manager.py
@@ -17,6 +17,8 @@
 
 """Style manager."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'StyleManager',
diff --git a/mailman/testing/helpers.py b/mailman/testing/helpers.py
index 9b5252b71..f92c5f012 100644
--- a/mailman/testing/helpers.py
+++ b/mailman/testing/helpers.py
@@ -17,6 +17,8 @@
 
 """Various test helpers."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'TestableMaster',
diff --git a/mailman/testing/layers.py b/mailman/testing/layers.py
index f3a4266fd..19300ba1e 100644
--- a/mailman/testing/layers.py
+++ b/mailman/testing/layers.py
@@ -17,6 +17,8 @@
 
 """Mailman test layers."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'ConfigLayer',
@@ -31,7 +33,6 @@ import logging
 import tempfile
 
 from pkg_resources import resource_string
-from string import Template
 from textwrap import dedent
 
 from mailman.config import config
@@ -39,6 +40,7 @@ from mailman.core import initialize
 from mailman.core.logging import get_handler
 from mailman.i18n import _
 from mailman.testing.helpers import SMTPServer
+from mailman.utilities.string import expand
 
 
 NL = '\n'
@@ -105,11 +107,11 @@ class ConfigLayer:
             # If stderr debugging is enabled, make sure subprocesses are also
             # more verbose.
             if cls.stderr:
-                test_config += Template(dedent("""
+                test_config += expand(dedent("""
                 [logging.$name]
                 propagate: yes
                 level: debug
-                """)).substitute(name=sub_name, path=path)
+                """), dict(name=sub_name, path=path))
         # zope.testing sets up logging before we get to our own initialization
         # function.  This messes with the root logger, so explicitly set it to
         # go to stderr.
@@ -170,7 +172,7 @@ class ConfigLayer:
         zc.testing package.  There should be a better way!
         """
         from zope.testing.testrunner.options import parser
-        parser.add_option('-e', '--stderr',
+        parser.add_option(str('-e'), str('--stderr'),
                           action='callback', callback=cls.handle_stderr,
                           help=_('Propagate log errors to stderr.'))
 
diff --git a/mailman/testing/mta.py b/mailman/testing/mta.py
index af1c19223..a10ba3c81 100644
--- a/mailman/testing/mta.py
+++ b/mailman/testing/mta.py
@@ -17,6 +17,8 @@
 
 """Fake MTA for testing purposes."""
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'FakeMTA',
diff --git a/mailman/testing/smtplistener.py b/mailman/testing/smtplistener.py
index f7f584f92..2094e20de 100644
--- a/mailman/testing/smtplistener.py
+++ b/mailman/testing/smtplistener.py
@@ -17,6 +17,14 @@
 
 """A test SMTP listener."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'Server',
+    ]
+
+
 import smtpd
 import socket
 import logging
@@ -71,7 +79,7 @@ class Server(smtpd.SMTPServer):
     def process_message(self, peer, mailfrom, rcpttos, data):
         """Process a message by adding it to the mailbox."""
         message = message_from_string(data)
-        message['X-Peer'] = '%s:%s' % peer
+        message['X-Peer'] = '{0}:{1}'.format(*peer)
         message['X-MailFrom'] = mailfrom
         message['X-RcptTo'] = COMMASPACE.join(rcpttos)
         log.info('[SMTPServer] processed message: %s',
diff --git a/mailman/tests/test_bounces.py b/mailman/tests/test_bounces.py
index 564c285c8..d5e525648 100644
--- a/mailman/tests/test_bounces.py
+++ b/mailman/tests/test_bounces.py
@@ -17,6 +17,14 @@
 
 """Test the bounce detection modules."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'test_suite',
+    ]
+
+
 import os
 import sys
 import email
diff --git a/mailman/tests/test_documentation.py b/mailman/tests/test_documentation.py
index b43b4378e..dd205c307 100644
--- a/mailman/tests/test_documentation.py
+++ b/mailman/tests/test_documentation.py
@@ -21,6 +21,8 @@ Note that doctest extraction does not currently work for zip file
 distributions.  doctest discovery currently requires file system traversal.
 """
 
+from __future__ import absolute_import, unicode_literals
+
 __metaclass__ = type
 __all__ = [
     'test_suite',
@@ -87,6 +89,19 @@ def stop():
     pdb.set_trace()
 
 
+def dump_msgdata(msgdata, *additional_skips):
+    """Dump in a more readable way a message metadata dictionary."""
+    skips = set(additional_skips)
+    # Some stuff we always want to skip, because their values will always be
+    # variable data.
+    skips.add('received_time')
+    longest = max(len(key) for key in msgdata if key not in skips)
+    for key in sorted(msgdata):
+        if key in skips:
+            continue
+        print '{0:{2}}: {1}'.format(key, msgdata[key], longest)
+
+
 def setup(testobj):
     """Test setup."""
     # In general, I don't like adding convenience functions, since I think
@@ -95,6 +110,7 @@ def setup(testobj):
     # hide some icky test implementation details.
     testobj.globs['commit'] = config.db.commit
     testobj.globs['config'] = config
+    testobj.globs['dump_msgdata'] = dump_msgdata
     testobj.globs['message_from_string'] = specialized_message_from_string
     testobj.globs['smtpd'] = SMTPLayer.smtpd
     testobj.globs['stop'] = stop
@@ -114,8 +130,6 @@ def test_suite():
     flags = (doctest.ELLIPSIS |
              doctest.NORMALIZE_WHITESPACE |
              doctest.REPORT_NDIFF)
-##     if config.tests.verbosity <= 2:
-##         flags |= doctest.REPORT_ONLY_FIRST_FAILURE
     # Add all the doctests in all subpackages.
     doctest_files = {}
     with chdir(topdir):
@@ -123,12 +137,6 @@ def test_suite():
             for filename in os.listdir(docsdir):
                 if os.path.splitext(filename)[1] == '.txt':
                     doctest_files[filename] = os.path.join(docsdir, filename)
-    # Sort or randomize the tests.
-##     if config.tests.randomize:
-##         files = doctest_files.keys()
-##         random.shuffle(files)
-##     else:
-##         files = sorted(doctest_files)
     files = sorted(doctest_files)
     for filename in files:
         path = doctest_files[filename]
diff --git a/mailman/tests/test_membership.py b/mailman/tests/test_membership.py
index fdb00eec9..9fa00867d 100644
--- a/mailman/tests/test_membership.py
+++ b/mailman/tests/test_membership.py
@@ -17,6 +17,14 @@
 
 """Unit tests for OldStyleMemberships."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'test_suite',
+    ]
+
+
 import time
 import unittest
 
diff --git a/mailman/tests/test_passwords.py b/mailman/tests/test_passwords.py
index b84307c19..d8d310f08 100644
--- a/mailman/tests/test_passwords.py
+++ b/mailman/tests/test_passwords.py
@@ -17,6 +17,14 @@
 
 """Unit tests for the passwords module."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'test_suite',
+    ]
+
+
 import unittest
 
 from mailman import passwords
diff --git a/mailman/tests/test_security_mgr.py b/mailman/tests/test_security_mgr.py
index a70129210..cdcd2021a 100644
--- a/mailman/tests/test_security_mgr.py
+++ b/mailman/tests/test_security_mgr.py
@@ -17,6 +17,14 @@
 
 """Unit tests for the SecurityManager module."""
 
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'test_suite',
+    ]
+
+
 import os
 import errno
 import unittest
diff --git a/mailman/utilities/__init__.py b/mailman/utilities/__init__.py
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/mailman/utilities/__init__.py
diff --git a/mailman/utilities/string.py b/mailman/utilities/string.py
new file mode 100644
index 000000000..2ca8c2021
--- /dev/null
+++ b/mailman/utilities/string.py
@@ -0,0 +1,59 @@
+# Copyright (C) 2009 by the Free Software Foundation, Inc.
+#
+# This file is part of GNU Mailman.
+#
+# GNU Mailman is free software: you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free
+# Software Foundation, either version 3 of the License, or (at your option)
+# any later version.
+#
+# GNU Mailman is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
+
+"""String utilities."""
+
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'expand'
+    ]
+
+
+import logging
+from string import Template
+
+log = logging.getLogger('mailman.error')
+
+
+
+def expand(template, substitutions, template_class=Template):
+    """Expand string template with substitutions.
+
+    :param template: A PEP 292 $-string template.
+    :type template: string
+    :param substitutions: The substitutions dictionary.
+    :type substitutions: dict
+    :param template_class: The template class to use.
+    :type template_class: class
+    :return: The substituted string.
+    :rtype: string
+    """
+    # Python 2.6 requires ** dictionaries to have str, not unicode keys, so
+    # convert as necessary.  Note that string.Template uses **.  For our
+    # purposes, keys should always be ascii.  Values though can be anything.
+    cooked = substitutions.__class__()
+    for key in substitutions:
+        if isinstance(key, unicode):
+            key = key.encode('ascii')
+        cooked[key] = substitutions[key]
+    try:
+        return template_class(template).safe_substitute(cooked)
+    except (TypeError, ValueError):
+        # The template is really screwed up.
+        log.exception('broken template: %s', template)
diff --git a/template.py b/template.py
new file mode 100644
index 000000000..709f4f7c4
--- /dev/null
+++ b/template.py
@@ -0,0 +1,24 @@
+# Copyright (C) 2009 by the Free Software Foundation, Inc.
+#
+# This file is part of GNU Mailman.
+#
+# GNU Mailman is free software: you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free
+# Software Foundation, either version 3 of the License, or (at your option)
+# any later version.
+#
+# GNU Mailman is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
+
+"""Module stuff."""
+
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    ]