PyCharm throws "AttributeError: 'module' object has no attribute" when running tests for no reason

So, I have a Django-REST Framework project and one day it simply ceased being able to run the tests within PyCharm.

From the command line I can run them both using paver or the manage.py directly.

There was a time when that would happen when we didn't import the class' superclass at the top of the file, but that's not the case.

We have a virtualenv set locally and run the server from a vagrant box. I assured the virtual environment is loaded and that the project's Interpreter is using the afore mentioned virtual env.

No clue on what's the matter.