You can use pkg_resources which comes with setuptools to look up the version number of your package in setup.py:

  import pkg_resources
  pkg_resources.get_distribution("PIL").version

I put the version information inside the package, then anything with access to the package (which both setup.py and sphinx have) can access it - quite useful for doing things like checking the version number from the REPL, for instance.

It can be problematic to import your package from setup.py if you want your dependency specification to be useful.