job_def2->mutable_tasks()->insert(
      {0, tensorflow::strings::StrCat(
              "localhost:", tensorflow::testing::PickUnusedPortOrDie())});
  return server_def;
}

// This test verifies the following:
// 1. Start the GRPC server for worker 1 using single host server def A with
//    only worker 1.
// 2. Create a context B using A.
// 3. Create the variable in B.