diff --git a/djblets/auth/forms.py b/djblets/auth/forms.py
index eab4b99cb4f91469d56094c98e2d373cac986a23..27ae7fb9d9363e0e074a007ef93c106590e801d7 100644
--- a/djblets/auth/forms.py
+++ b/djblets/auth/forms.py
@@ -30,7 +30,6 @@ from django import forms
 from django.contrib import auth
 from django.contrib.auth.models import User
 from django.core.exceptions import ValidationError
-from django.utils import six
 from django.utils.translation import ugettext_lazy as _
 
 from djblets.db.query import get_object_or_none
diff --git a/djblets/extensions/forms.py b/djblets/extensions/forms.py
index b24f72e5dfbe3c69ed23f577b3708191f1dc29aa..3c96391d7ad3586ba8bae89aa8559b4b96c26c51 100644
--- a/djblets/extensions/forms.py
+++ b/djblets/extensions/forms.py
@@ -25,8 +25,6 @@
 
 from __future__ import unicode_literals
 
-from django import forms
-
 from djblets.siteconfig.forms import SiteSettingsForm
 
 
diff --git a/djblets/extensions/manager.py b/djblets/extensions/manager.py
index e7118bb9d731ebfe0d20cb4b6304306cbc5cc8d5..b18c3d939e0939c1cc66f94495dfd151929f5dfa 100644
--- a/djblets/extensions/manager.py
+++ b/djblets/extensions/manager.py
@@ -103,10 +103,9 @@ class SettingListWrapper(object):
             self.ref_counts[item] += 1
         else:
             assert item not in self.setting, \
-                   ("%s extension's %s %s is already in settings.%s, with "
+                   ("Extension's %s %s is already in settings.%s, with "
                     "ref count of 0."
-                    % (extension.id, self.display_name, item,
-                       self.setting_name))
+                    % (self.display_name, item, self.setting_name))
 
             self.ref_counts[item] = 1
             self.setting.append(item)
@@ -123,11 +122,11 @@ class SettingListWrapper(object):
         be removed from the list.
         """
         assert item in self.ref_counts, \
-               ("%s extension's %s %s is missing a ref count."
-                % (extension.id, self.display_name, item))
+               ("Extension's %s %s is missing a ref count."
+                % (self.display_name, item))
         assert item in self.setting, \
-               ("%s extension's %s %s is not in settings.%s"
-                % (extension.id, self.display_name, item, self.setting_name))
+               ("Extension's %s %s is not in settings.%s"
+                % (self.display_name, item, self.setting_name))
 
         if self.ref_counts[item] == 1:
             del self.ref_counts[item]
diff --git a/djblets/extensions/staticfiles.py b/djblets/extensions/staticfiles.py
index 0f92d40856494e68c5a83acfe454b2d69ec5c253..b02b37b8e2b98e9066c659aad932c57f362ec4c4 100644
--- a/djblets/extensions/staticfiles.py
+++ b/djblets/extensions/staticfiles.py
@@ -2,12 +2,11 @@ from __future__ import unicode_literals
 
 import os
 
-from django.contrib.staticfiles.finders import (BaseFinder, FileSystemFinder,
-                                                get_finder)
+from django.contrib.staticfiles.finders import BaseFinder, FileSystemFinder
 from django.contrib.staticfiles.utils import get_files
 from django.core.files.storage import FileSystemStorage
 from pipeline.storage import PipelineFinderStorage
-from pkg_resources import resource_exists, resource_filename
+from pkg_resources import resource_filename
 
 from djblets.extensions.manager import get_extension_managers
 
diff --git a/djblets/extensions/tests.py b/djblets/extensions/tests.py
index 432b447de255b0aa08afbeeb847a7582fd8b5612..9ee1f62f5a1728677173d34409c83680ad092fab 100644
--- a/djblets/extensions/tests.py
+++ b/djblets/extensions/tests.py
@@ -112,7 +112,6 @@ class SettingsTest(TestCase):
 
         settings_saved.connect(on_settings_saved, sender=self.extension)
 
-        registration = self.extension.registration
         self.settings['test_new_key'] = 'Test new value'
         self.settings.save()
 
diff --git a/djblets/util/tests.py b/djblets/util/tests.py
index 0679527d7b20637c27dc984e1669c919697aec6a..b0954eccca529327959d03236e21f6a9065b4748 100644
--- a/djblets/util/tests.py
+++ b/djblets/util/tests.py
@@ -30,7 +30,6 @@ import unittest
 
 from django.conf import settings
 from django.conf.urls import include, patterns, url
-from django.contrib.sites.models import Site
 from django.core.cache import cache
 from django.core.exceptions import ValidationError
 from django.core.urlresolvers import NoReverseMatch, reverse