ASSERT_EQ(TF_GetCode(status), TF_OK) << TF_Message(status);

  // Register and run a function which returns the sum of 3 variables.
  const string function_def = AddVariablesFunction();
  TFE_ContextAddFunctionDef(ctx, function_def.data(), function_def.size(),
                            status);
  ASSERT_EQ(TF_GetCode(status), TF_OK) << TF_Message(status);

  TFE_Op* func = TFE_NewOp(ctx, "AddVariablesFunction", status);

          unwrapped_ctx, tensorflow::unwrap(h), device_name, &status->status);

  if (status->status.ok()) {
    return tensorflow::wrap(result);
  }
  return nullptr;
}

void TFE_ContextAddFunctionDef(TFE_Context* ctx,
                               const char* serialized_function_def, size_t size,
                               TF_Status* status) {
  tensorflow::FunctionDef function_def;