diff --git a/openslides/motion/models.py b/openslides/motion/models.py
index f0d4653d8..ad2be5a81 100644
--- a/openslides/motion/models.py
+++ b/openslides/motion/models.py
@@ -15,8 +15,6 @@
 
 from datetime import datetime
 
-import difflib
-
 from django.core.urlresolvers import reverse
 from django.db import models, IntegrityError
 from django.db.models import Max
diff --git a/openslides/motion/views.py b/openslides/motion/views.py
index e55e556b6..4a233436f 100644
--- a/openslides/motion/views.py
+++ b/openslides/motion/views.py
@@ -251,7 +251,7 @@ class VersionRejectView(GetVersionMixin, SingleObjectMixin, QuestionMixin, Redir
 version_reject = VersionRejectView.as_view()
 
 
-class VersionDiffView(GetVersionMixin, DetailView):
+class VersionDiffView(DetailView):
     """Show diff between two versions of a motion."""
     permission_required = 'motion.can_see_motion'
     model = Motion
diff --git a/openslides/utils/utils.py b/openslides/utils/utils.py
index 26c31aac5..da29ab8b3 100644
--- a/openslides/utils/utils.py
+++ b/openslides/utils/utils.py
@@ -10,8 +10,9 @@
     :license: GNU GPL, see LICENSE for more details.
 """
 
-import sys
+import difflib
 import json
+import sys
 
 from django.contrib import messages
 from django.contrib.auth.models import Permission
@@ -156,7 +157,7 @@ def html_strong(string):
     return u"<strong>%s</strong>" % string
 
 
-def htmldiff(self, rev1, rev2):
+def htmldiff(rev1, rev2):
     """Return string of html diff between two strings (rev1 and rev2)"""
 
     diff = difflib.HtmlDiff(wrapcolumn=60)