Fixes "is not" usage

Fixes bug #1110973

Change-Id: I68451ce32f3036e43a2bf1f59a02b392a9e40d6d

nova/api/ec2/cloud.py

@@ -407,7 +407,7 @@ class CloudController(object):
 
     def describe_key_pairs(self, context, key_name=None, **kwargs):
         key_pairs = self.keypair_api.get_key_pairs(context, context.user_id)
-        if not key_name is None:
+        if key_name is not None:
             key_pairs = [x for x in key_pairs if x['name'] in key_name]
 
         #If looking for non existent key pair

nova/common/memorycache.py

@@ -70,7 +70,7 @@ class Client(object):
 
     def add(self, key, value, time=0, min_compress_len=0):
         """Sets the value for a key if it doesn't exist."""
-        if not self.get(key) is None:
+        if self.get(key) is not None:
             return False
         return self.set(key, value, time, min_compress_len)
 

nova/tests/api/openstack/fakes.py

@@ -399,12 +399,12 @@ def fake_instance_get_all_by_filters(num_servers=5, **kwargs):
             server = stub_instance(id=i + 1, uuid=uuid,
                     **kwargs)
             servers_list.append(server)
-            if not marker is None and uuid == marker:
+            if marker is not None and uuid == marker:
                 found_marker = True
                 servers_list = []
-        if not marker is None and not found_marker:
+        if marker is not None and not found_marker:
             raise exc.MarkerNotFound(marker=marker)
-        if not limit is None:
+        if limit is not None:
             servers_list = servers_list[:limit]
         return servers_list
     return _return_servers

nova/utils.py

@@ -628,7 +628,7 @@ class DynamicLoopingCall(LoopingCallBase):
                     if not self._running:
                         break
 
-                    if not periodic_interval_max is None:
+                    if periodic_interval_max is not None:
                         idle = min(idle, periodic_interval_max)
                     LOG.debug(_('Periodic task processor sleeping for %.02f '
                                 'seconds'), idle)

nova/virt/libvirt/imagecache.py

@@ -464,7 +464,7 @@ class ImageCacheManager(object):
             # _verify_checksum returns True if the checksum is ok, and None if
             # there is no checksum file
             checksum_result = self._verify_checksum(img_id, base_file)
-            if not checksum_result is None:
+            if checksum_result is not None:
                 image_bad = not checksum_result
 
             # Give other threads a chance to run