diff --git a/plinth/modules/apps/apps.py b/plinth/modules/apps/apps.py
index f935c21af..534269cfc 100644
--- a/plinth/modules/apps/apps.py
+++ b/plinth/modules/apps/apps.py
@@ -23,7 +23,8 @@ from plinth import cfg
 
 def init():
     """Initailize the apps module"""
-    cfg.main_menu.add_urlname("Apps", "glyphicon-download-alt", "apps:index", 80)
+    cfg.main_menu.add_urlname("Apps", "glyphicon-download-alt", "apps:index",
+                              80)
 
 
 def index(request):
diff --git a/plinth/modules/diagnostics/diagnostics.py b/plinth/modules/diagnostics/diagnostics.py
index 953c67c2c..808a51404 100644
--- a/plinth/modules/diagnostics/diagnostics.py
+++ b/plinth/modules/diagnostics/diagnostics.py
@@ -31,7 +31,8 @@ from plinth.errors import ActionError
 def init():
     """Initialize the module"""
     menu = cfg.main_menu.get('system:index')
-    menu.add_urlname("Diagnostics", "glyphicon-screenshot", "diagnostics:index", 30)
+    menu.add_urlname("Diagnostics", "glyphicon-screenshot",
+                     "diagnostics:index", 30)
 
 
 @login_required
diff --git a/plinth/modules/system/system.py b/plinth/modules/system/system.py
index 9f57fa91e..0fce8278b 100644
--- a/plinth/modules/system/system.py
+++ b/plinth/modules/system/system.py
@@ -23,7 +23,8 @@ from plinth import cfg
 
 def init():
     """Initialize the system module"""
-    cfg.main_menu.add_urlname(_('System'), 'glyphicon-cog', 'system:index', 100)
+    cfg.main_menu.add_urlname(_('System'), 'glyphicon-cog', 'system:index',
+                              100)
 
 
 def index(request):
diff --git a/plinth/service.py b/plinth/service.py
index cd8d40aab..a9db56f27 100644
--- a/plinth/service.py
+++ b/plinth/service.py
@@ -21,7 +21,6 @@ Framework for working with servers and their services.
 
 from gettext import gettext as _
 
-import django.dispatch
 import collections
 
 from plinth.signals import service_enabled
@@ -66,7 +65,7 @@ class Service(object):
             self._enabled = enabled
 
         service_enabled.send_robust(sender=sender, service_id=self.service_id,
-                            enabled=enabled)
+                                    enabled=enabled)
 
 
 def init():