Black - Code Formatting

[Zarathustra2]

Maybe we should add formatting rules to this project for example: Black

[cb109]

I agree, especially since Django will also do this once black is stable (https://github.com/django/deps/blob/master/accepted/0008-black.rst). I am currently getting some experience with this, I think it would be nice to set this up as a https://pre-commit.com/ hook which has builtin support for black.