Fix exception when doing volume set operation

Xi Yang · Xi Yang · commit 197d86dffa4b · 2015-12-03T15:25:12.000+08:00
The v2 SetVolume extends from show.ShowOne and returns None
after setting volume operation. It will raise an exception.
This patch is going to fix the issue by changing the parent
class of SetVolume to command.Command.

Change-Id: Iefa453fe4adad06f2a0601a052c01e74004be5b7
Closes-bug: 1521896
diff --git a/openstackclient/volume/v2/volume.py b/openstackclient/volume/v2/volume.py
@@ -326,7 +326,7 @@ def _format_attach(attachments):
                 ) for s in data))
 
 
-class SetVolume(show.ShowOne):
+class SetVolume(command.Command):
     """Set volume properties"""
 
     log = logging.getLogger(__name__ + '.SetVolume')
