const string& op_name) {
  std::vector<int64_t> input_ids(inputs.size());
  std::vector<tensorflow::DataType> input_dtypes(inputs.size());
  for (int i = 0; i < inputs.size(); i++) {
    input_ids[i] = ToId(inputs[i]);
    input_dtypes[i] = inputs[i]->DataType();
  }
  std::vector<TapeTensor> tape_tensors;
  tape_tensors.reserve(outputs.size());
  for (auto t : outputs) {

}

int TF_OperationNumInputs(TF_Operation* oper) {
  return oper->node.num_inputs();
}

TF_DataType TF_OperationInputType(TF_Input oper_in) {
  return static_cast<TF_DataType>(oper_in.oper->node.input_type(oper_in.index));
}

int TF_OperationInputListLength(TF_Operation* oper, const char* arg_name,
                                TF_Status* status) {
  NameRangeMap name_ranges;
  status->status =