Flake8 + Black

[multiflexi]

Would you be against adding Flake8 to .pre-commit.yaml and setting the width of line in both Black and Flake8 to some higher number than 80? E.g. 120?

[multiflexi]

I just found out that in pyproject.toml its already set to 142. That is also fine by me.

[multiflexi]

It is part of #155