当我们使用Google协议缓冲区时，可以修改生成的pb.go文件吗？

For example, is it ok to add an interface or associate a function I created with a struct in the generated pb.go file?

The reason that I want to make these kinds of changes is it would make my code easier to implement. I am not sure if I am allowed to do this since the first commented line in the generated file says "DO NOT EDIT".