Fake module for autocomplete support

Hi guys. My problem is that I have a python module that is loaded using a C ++ library. In the end, I get the module, but the auto-completion does not work. I would like to write ... maybe a plugin, maybe the class is a stub, where all the comments I need are present, which will provide support for autocompletion. A more acceptable option for me would be to write a stub class. But I do not know how to start, tell me where to dig into the solution of this problem?