[kennydude]

If you're using Django, Python Social Auth tends to go a good job at this without any extra servers.

[clintonb]

PSA is a collection of authentication clients for authenticating with third-party auth providers (e.g. Google, Facebook, Microsoft). If you want to run your own auth provider server, you will need another library. We use Django OAuth Toolkit (https://github.com/evonove/django-oauth-toolkit) at edX.