diff --git a/synergy/common/context.py b/synergy/common/context.py
index b4cad8e..cf2e96d 100644
--- a/synergy/common/context.py
+++ b/synergy/common/context.py
@@ -124,7 +124,7 @@ class RequestContext(object):
 
         return cls(**values)
 
-    def elevated(self, read_deleted=None, overwrite=False):
+    def elevated(self, read_deleted=None):
         """Return a version of this context with admin flag set."""
         context = copy.copy(self)
         context.is_admin = True
diff --git a/synergy/common/manager.py b/synergy/common/manager.py
index 20d1e8e..8c828dc 100644
--- a/synergy/common/manager.py
+++ b/synergy/common/manager.py
@@ -38,13 +38,13 @@ class Manager(Thread):
         self.managers = {}
 
     def execute(self, command, *args, **kargs):
-        pass
+        raise NotImplementedError
 
     def task(self):
-        pass
+        raise NotImplementedError
 
     def doOnEvent(self, event_type, *args, **kargs):
-        pass
+        raise NotImplementedError
 
     def getManagers(self):
         return self.managers
@@ -88,10 +88,10 @@ class Manager(Thread):
         is created.
         Child classes should override this method.
         """
-        pass
+        raise NotImplementedError
 
     def destroy(self):
-        pass
+        raise NotImplementedError
 
     def getStatus(self):
         return self.status
diff --git a/synergy/common/serializer.py b/synergy/common/serializer.py
index 9e40bf7..c9665e1 100644
--- a/synergy/common/serializer.py
+++ b/synergy/common/serializer.py
@@ -106,7 +106,7 @@ class SynergyObject(object):
 
 class SynergySerializer(oslo_messaging.Serializer):
     def __init__(self):
-        super(oslo_messaging.Serializer, self).__init__()
+        super(SynergySerializer, self).__init__()
 
     def serialize_entity(self, context, entity):
         if not entity:
diff --git a/synergy/common/service.py b/synergy/common/service.py
index a014f7c..be7568e 100644
--- a/synergy/common/service.py
+++ b/synergy/common/service.py
@@ -38,7 +38,7 @@ class Service(object):
         signal.signal(signal.SIGTERM, self.sigterm_handler)
         signal.signal(signal.SIGINT, self.sigterm_handler)
 
-    def sigterm_handler(self, signum, frame):
+    def sigterm_handler(self):
         global SIGTERM_SENT
         if not SIGTERM_SENT:
             LOG.info("Shutting down %s" % self.name)
@@ -52,13 +52,13 @@ class Service(object):
         return self.name
 
     def start(self):
-        pass
+        raise NotImplementedError
 
     def stop(self):
-        pass
+        raise NotImplementedError
 
     def wait(self):
-        pass
+        raise NotImplementedError
 
     def restart(self):
         # Reload config files and restart service
diff --git a/synergy/common/utils.py b/synergy/common/utils.py
index 2567894..0b209cb 100644
--- a/synergy/common/utils.py
+++ b/synergy/common/utils.py
@@ -28,6 +28,6 @@ def import_class(import_str):
     try:
         return getattr(sys.modules[mod_str], class_str)
     except AttributeError:
-        raise ImportError('Class %s cannot be found (%s)' %
-                          (class_str,
-                           traceback.format_exception(*sys.exc_info())))
+        raise ImportError(
+            'Class %s cannot be found (%s)' %
+            (class_str, traceback.format_exception(*sys.exc_info())))
diff --git a/synergy/service.py b/synergy/service.py
index d0d88c6..05bc820 100644
--- a/synergy/service.py
+++ b/synergy/service.py
@@ -73,7 +73,6 @@ class ManagerRPC(object):
                               % (ex))
 
                     result[name] = manager.getStatus()
-                    pass
 
         return result
 
@@ -97,7 +96,6 @@ class ManagerRPC(object):
                               % (ex))
 
                     result[name] = manager.getStatus()
-                    pass
 
         return result
 
@@ -367,7 +365,6 @@ class Synergy(service.Service):
                                   "%s" % (ex))
 
                         result[name]["message"] = "ERROR: %s" % ex
-                        pass
                 else:
                     result[name]["message"] = "WARN: already started"
 
@@ -416,7 +413,6 @@ class Synergy(service.Service):
                                   % (ex))
 
                         result[name]["message"] = "ERROR: %s" % ex
-                        pass
                 else:
                     result[name]["message"] = "WARN: already stopped"