code: def logged_in(self):
          
          try:
              self._proxy.User.get({'ids': []})
              return True
          except Fault as e:
              if e.faultCode == 505 or e.faultCode == 32000:
                  return False
              raise e
docs: This is True if this instance is logged in else False.
  
          We test if this session is authenticated by calling the User.get()
          XMLRPC method with ids set. Logged-out users cannot pass the 'ids'
          parameter and will result in a 505 error. If we tried to login with a
          token, but the token was incorrect or expired, the server returns a
          32000 error.
  
          For Bugzilla 5 and later, a new method, User.valid_login is available
          to test the validity of the token. However, this will require that the
          username be cached along with the token in order to work effectively in
          all scenarios and is not currently used. For more information, refer to
          the following url.
  
          http://bugzilla.readthedocs.org/en/latest/api/core/v1/user.html#valid-login