希望提供com.ikurento.user.Response<T> Go client例子

com.ikurento.user.UserProvider#Sum,返回值com.ikurento.user.Response对应的go client应该怎么写通用的例子，我测试时，将Response中的Data写成固定类型是可以接受参数的，但是怎么实现泛型呢。

Start with the com.ikurento.user.UserProvider#Sum method and its com.ikurento.user.Response return type. Determine where Go client examples for this sample belong and how the current fixed Data type is handled. Done means the sample documents a runnable, reusable Go client example for the generic response.

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