PEP8 cleanups, remove unused imports

apps/common/__init__.py

@@ -5,7 +5,6 @@ import tempfile
 from django.utils.translation import ugettext_lazy as _
 from django.contrib.auth import models as auth_models
 from django.contrib.auth.management import create_superuser
-from django.db.models import signals
 from django.dispatch import receiver
 from django.db.models.signals import post_syncdb
 

apps/common/widgets.py

@@ -120,7 +120,8 @@ class ScrollableCheckboxSelectMultiple(forms.widgets.CheckboxSelectMultiple):
     exceds the height of the div
     '''
     def render(self, name, value, attrs=None, choices=()):
-        if value is None: value = []
+        if value is None:
+            value = []
         has_id = attrs and 'id' in attrs
         final_attrs = self.build_attrs(attrs, name=name)
         output = [u'<ul class="undecorated_list" style="margin-left: 5px; margin-top: 3px; margin-bottom: 3px;">']