To use Django with python social auth, you need to install the Django app as well.
You can specify that you want to install the extra requirements for Django when you install python-social-auth
:
pip install python-social-auth[django]
Or, in this case, you can install the missing package individually:
pip install social-auth-app-django
Probably you should use pip 3:
pip3 install social-auth-app-django