Deploy module to specific directory when deploying with setuptools

[caffeinism]

I'm in a situation where I have a mix of python and c++ modules. But I don't want to export the c++ module outside of one module, so I want to use it as a submodule of my python module. This is the deployment situation I think.

mypymodule
⌊__init__.py
⌊mypysubmodule1
⌊mypysubmodule2
⌊mycppsubmodule1
...

However, when deploying with setuptools, the cpp module is always deployed on top of the module. Any solution? I think you did a lot of searching. But I can't find a way.