Introduce black & fix flake8

[kellerza]

Would you be interested to introduce black for code formatting?

Black fixes the majority of the flake8 issue present in the library today: blanks lines at the end of files, too many blank lines, visual indents, etc

Although Black requires Python 3 to run, it can safely format code for Python 2 and execute as a pre-commit hook.

To implement the Black fixes, you can execute the following:

pip install pre-commit
pre-commit install
pre-commit run --all

You can see an example of changes here - but this will be a PITA to review, so it's probably best that you do the initial Black run and commit it before we continue

[kellerza]

This also adds isort to sort & group import statements

[vgrem]

Greetings,

thank you for the suggestion! Perhaps IDE could do the job in terms of runing pre-commit within the IDE instead of triggering it manually, for instance PyCharm supports Black formatter integration Lets give it a try.

[kellerza]

It should be consistent if you do it via the IDE (pycharm/vscode) and pre-commit (black has almost no settings)

The nice thing about pre-commit is that its a hook on "git commit" that just ensures this irrespective of your IDE.