Python: 'Private' module in a package

Question

I have a package mypack with modules mod_a and mod_b in it. I intend the the package itself and mod_a to be imported free

Answer 1

I prefix private modules with an underscore to communicate the intent to the user. In your case, this would be mypack._mod_b

This is in the same spirit (but not completely analogous to) the PEP8 recommendation to name C-extension modules with a leading underscore when it’s wrapped by a Python module; i.e., _socket and socket.