Preventing namespace collisions between private and pypi-based Python packages

It might not be the solution for you, but I tell what we do.

1. Prefix the package names, and using namespaces (eg. company.product.tool).
2. When we install our packages (including their in-house dependencies), we use a requirements.txt file including our PyPI URL. We run everything in container(s) and we install all public dependencies in them when we are building the images.