Also, this isn't relevant given my below comment suggesting that `google_api.py` shouldn't be in this folder, but doing implicit relative imports like this is a little dangerous, and you should in the future do explicit relative imports::

    from . import google_api

or just address modules absolutely:

    from django_mailbox.transports import google_api
    # or
    import django_mailbox.transports.google_api

Also -- to clarify my above comment (now that I've re-read it, it doesn't sound clear) -- I was referring to adding `python-social-auth` as a requirement in `setup.py`'s `extras_require`.