}
    TF_Status* s = TF_NewStatus();
    auto* operation = TF_FinishOperation(tf_opdesc, s);
    TF_RETURN_IF_ERROR(StatusFromTF_Status(s));
    TF_DeleteStatus(s);
    *num_retvals = TF_OperationNumOutputs(operation);
    for (int i = 0; i < *num_retvals; ++i) {
      retvals[i] = new GraphTensor({operation, i}, g_);
    }
    return absl::OkStatus();
  }

  EXPECT_EQ(std::string("Placeholder"), std::string(TF_OperationOpType(feed)));
  EXPECT_EQ(std::string(""), std::string(TF_OperationDevice(feed)));
  EXPECT_EQ(1, TF_OperationNumOutputs(feed));
  EXPECT_EQ(TF_INT32, TF_OperationOutputType(TF_Output{feed, 0}));
  EXPECT_EQ(1, TF_OperationOutputListLength(feed, "output", s));
  ASSERT_EQ(TF_OK, TF_GetCode(s)) << TF_Message(s);

  return oper->node.type_string().c_str();
}

const char* TF_OperationDevice(TF_Operation* oper) {
  return oper->node.requested_device().c_str();
}

int TF_OperationNumOutputs(TF_Operation* oper) {
  return oper->node.num_outputs();
}

TF_DataType TF_OperationOutputType(TF_Output oper_out) {
  return static_cast<TF_DataType>(