std::string cpu0_device;
  if (failed(tensorflow::GetNonReplicatedCPU0(op, &cpu0_device)))
    return failure();
  if (device_str != tensorflow::GetDeviceAliasForHostOfLogicalCore(0) &&
      device_str != cpu0_device) {
    op->emitError()
        << "TPUCopyWithDynamicShapeOp's device is not a recognized host 0: "
        << device_str;
    return failure();
  }