Unit testing your models in Django As a good developer, you write unit tests, of course. You will probably even write your tests before implementing your logic in a test-driven approach! However, when developing complex models which have interactions and foreign keys, writing tests can get messy and complicated. Say you want to test a model which has many dependencies to other models via foreign keys. To create an instance of your model, you first need to create all the other model instances which your model uses and that can be pretty tiring.