How do you find a test that doesn't clean up after itself?

Question

Django

There is a big django project. A number of pytest tests have been written. Tests load fixtures before starting. And after running the tests, some fixtures are not removed. How to find what is the problem?
Tests are chasing postgres if that's important. Python 3.6, Django 2.1.

Answer 1

I rewrote the tests from classes to simple functions, everything worked as it should.

Answer 2

Debug.