def _get_tpu_system_metadata(self): """Gets the (maybe cached) TPU system metadata.""" master = self._get_master_address() tpu_system_metadata = self._lazy_tpu_system_metadata_dict.get(master) if tpu_system_metadata is not None: return tpu_system_metadata tpu_system_metadata = ( tpu_system_metadata_lib._TPUSystemMetadata( # pylint: disable=protected-access num_cores=1, num_hosts=1, num_of_cores_per_host=1, topology=None, devices=[])) self._lazy_tpu_system_metadata_dict[master] = tpu_system_metadata return tpu_system_metadata