TF_Buffer* metagraph = TF_NewBuffer();
  TF_Status* s = TF_NewStatus();
  const char* tags[] = {tensorflow::kSavedModelTagServe};
  TF_Graph* graph = TF_NewGraph();
  TF_Session* session = TF_LoadSessionFromSavedModel(
      opt, run_options, saved_model_dir.c_str(), tags, 1, graph, metagraph, s);
  TF_DeleteBuffer(run_options);
  TF_DeleteSessionOptions(opt);
  tensorflow::MetaGraphDef metagraph_def;