docs: def _get_client(self):
          """
          OSS2 Auth client
  
          Returns:
              oss2.Auth or oss2.StsAuth: client
          """
          return (_oss.StsAuth if 'security_token' in self._storage_parameters
                  else _oss.Auth if self._storage_parameters
                  else _oss.AnonymousAuth)(**self._storage_parameters)