Apply general spring style formatting 🌻

[bonjourmauko]

Spring is here

• Apply flake8-bugbear recommendations

[Morendil]

I'm 👍 on adding bugbear and following its recommendations, 👎 on "general formatting changes" which make this a very noisy PR (lots of conflict management to be expected with other long-running branches) and contain changes not mandated by our official linting checks.

[bonjourmauko]

Hi @Morendil !

I'm 👍 on adding bugbear and following its recommendations

I'll split in two different pull requests.

Make this a very noisy PR

What could we do to solve that issue? Split in several different pull requests? Or maybe it is just not worth the effort and we should live with it.

contain changes not mandated by our official linting checks

I did a catch-all to go fast so there maybe some errors.

My objective is to:

• Correct no spaces around = : this is not enforceable and is not PEP endorsed, but it is the style used majoritarily by this repo.

• Correct hang-closing indentation : here again, auto-formatter do not enforce rules 100% of the time.

I'm OK removing all the rest.

Those changes, AFAIK, are the ones we would like to enforce, will our linting checks allow us to (see #706 and openfisca/openfisca-france#1060).

[Morendil]

What could we do to solve that issue?

My best suggestion is to make the changes when you touch these files for some other reason. This spreads the changes over time and keeps them correlated with functional changes.