Black integration, fixes #1662

[ThomasWaldmann]

https://pypi.org/project/black/

[ThomasWaldmann]

@RogerHaase @UlrichB22 See the ran black on all python code commit about how it would look like.

[ThomasWaldmann]

BTW, we should decide about this rather quickly - this PR is likely conflicting with other PRs a lot.

[UlrichB22]

IMO the line-length should be set to about 120. It looks like you already specified it, but I did not find the config.
For me it is ok to integrate black.

[ThomasWaldmann]

@UlrichB22 It's there: d6e2137

[ThomasWaldmann]

@RogerHaase can you have a look?

if there are no objections to the black style, i'ld like to merge this (and also add pre-commit integration of it).

[RogerHaase]

Looks OK to me.

[ThomasWaldmann]

rebased onto current master.

[ThomasWaldmann]

@RogerHaase @UlrichB22 please run this in your workdir after this is merged into master and you updated your local master from github:

# additionally install pre-commit:
pip install -r requirements.d/development.txt

# add the pre-commit hook, invoking black and flake8:
pre-commit install

If e.g. black has to auto-format something in the pre-commit phase, it aborts the commit.

Then you can have a look at the changes (if you like), git add these changes and try committing again (which then should succeed).

[ThomasWaldmann]

squashed together some of the commits. ^^^