code: def delete_group_maintainer(self, grp_name, user):
          
          self.service.delete_group_maintainer(
              grp_name, user, self.url_prefix, self.auth, self.session,
              self.session_send_opts)
docs: Delete the given user to the named group.
  
          Both group and user must already exist for this to succeed.
  
          Args:
              name (string): Name of group.
              user (string): User to add to group.
  
          Raises:
              requests.HTTPError on failure.