const int port = tensorflow::testing::PickUnusedPortOrDie();
  job_def->mutable_tasks()->at(task_index) =
      tensorflow::strings::StrCat("localhost:", port);
  return server_def_copy;
}

void ReplaceTaskInServerDef(tensorflow::ServerDef* server_def, int task_index,
                            const string& host, int port) {
  tensorflow::JobDef* job_def = server_def->mutable_cluster()->mutable_job(0);