Python analog of Unix 'which'

If you do:

modulename.__file__

You will get a full path return of that exact module. For example, importing django:

>>>> import django
>>> django.__file__
'/home/bartek/.virtualenvs/safetyville/lib/python2.6/site-packages/django/__init__.pyc'

Edit: I recommend seeing the comments below for some good insight if you haven't had a chance to.