diff --git a/kallithea/model/pull_request.py b/kallithea/model/pull_request.py
--- a/kallithea/model/pull_request.py
+++ b/kallithea/model/pull_request.py
@@ -25,21 +25,19 @@ Original author and date, and relevant c
 :license: GPLv3, see LICENSE.md for more details.
 """
 
+import datetime
 import logging
-import datetime
 import re
 
+from sqlalchemy.orm import joinedload
 from tg import request
 from tg.i18n import ugettext as _
 
-from sqlalchemy.orm import joinedload
-
+from kallithea.lib import helpers as h
+from kallithea.lib.utils2 import extract_mentioned_users, safe_str, safe_unicode
+from kallithea.model.db import ChangesetStatus, PullRequest, PullRequestReviewer, User
 from kallithea.model.meta import Session
-from kallithea.lib import helpers as h
-from kallithea.model.db import PullRequest, PullRequestReviewer, \
-    ChangesetStatus, User
 from kallithea.model.notification import NotificationModel
-from kallithea.lib.utils2 import extract_mentioned_users, safe_str, safe_unicode
 
 
 log = logging.getLogger(__name__)