Several important cleanups.

* Turn on absolute_import and unicode_literals everywhere, and deal with the
  aftermath.
* Use 'except X as Y' everywhere.
* Make the module prologues much more consistent.
* Use '{}'.format() consistently, except for logger interface.
* Because of the problems with calling ** args with unicode keywords, hide
  calls to Template.substitute() behind an API.

28 files changed, 198 insertions, 5 deletions

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