return func->record->fdef().signature().name().c_str();
}

void TF_GraphCopyFunction(TF_Graph* g, const TF_Function* func,
                          const TF_Function* grad, TF_Status* status) {
  if (func == nullptr) {
    status->status = InvalidArgument(
        "'func' argument to TF_GraphCopyFunction cannot be null");
    return;
  }

  tensorflow::mutex_lock l(g->mu);

// If `grad` is null and `func` is in `g`, TF_GraphCopyFunction is a noop.
// `grad` must have appropriate signature as described in the doc of
// GradientDef in tensorflow/core/framework/function.proto.
//
// If successful, status is set to OK and `func` and `grad` are added to `g`.
// Otherwise, status is set to the encountered error and `g` is unmodified.
TF_CAPI_EXPORT extern void TF_GraphCopyFunction(TF_Graph* g,