You can also take a look on https://github.com/onelogin/python-saml
Is also open source and the toolkit contains 2 demos: A django application and a Flask application.
Right now only works on Python 2.X
Edited 13/05/2015: There is a python 3.X version (beta, I'm still testing it): https://github.com/pitbulk/python3-saml (thanks bgaifullin for contributing it)
Edited 13/04/2016: Python 3.X version is stable and tested.