title: NoneType' object has no attribute '__getitem__'
body: <p>I am getting the following error while trying nova-list cli command in an openstack setup.
  NoneType' object has no attribute '<strong>getitem</strong>'</p>
  
  <pre><code> DEBUG (shell:777) 'NoneType' object has no attribute '__getitem__'
      Traceback (most recent call last):
        File "/opt/stack/python-novaclient/novaclient/shell.py", line 774, in main
          OpenStackComputeShell().main(map(strutils.safe_decode, sys.argv[1:]))
        File "/opt/stack/python-novaclient/novaclient/shell.py", line 685, in main
          self.cs.authenticate()
        File "/opt/stack/python-novaclient/novaclient/v1_1/client.py", line 169, in authenticate
          self.client.authenticate()
        File "/opt/stack/python-novaclient/novaclient/client.py", line 382, in authenticate
          auth_url = self._v2_auth(auth_url)
        File "/opt/stack/python-novaclient/novaclient/client.py", line 469, in _v2_auth
          return self._authenticate(url, body)
        File "/opt/stack/python-novaclient/novaclient/client.py", line 484, in _authenticate
          return self._extract_service_catalog(url, resp, respbody)
        File "/opt/stack/python-novaclient/novaclient/client.py", line 307, in _extract_service_catalog
          self.auth_token = self.service_catalog.get_token()
        File "/opt/stack/python-novaclient/novaclient/service_catalog.py", line 29, in get_token
          return self.catalog['access']['token']['id']
      TypeError: 'NoneType' object has no attribute '__getitem__'
      ERROR: 'NoneType' object has no attribute '__getitem_
  </code></pre>
  
  <p>_'</p>
  
  <p>What does that mean?Is there any problem with my openstack setup or it's some python related error?</p>