Finish pep8 compliance

[mfeurer]

No description provided.

[codecov-io]

Codecov Report

Merging #630 into develop will not change coverage.
The diff coverage is n/a.

@@ Coverage Diff @@## develop #630 +/- ##
========================================
Coverage 89.86% 89.86% ========================================
Files 32 32 Lines 3208 3208 ========================================
Hits 2883 2883 Misses 325 325

Impacted Files	Coverage Δ
openml/datasets/__init__.py	100% <ø> (ø)	⬆️

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[janvanrijn]

The PR looks mainly great to me. Can you explain why the script flake8_diff.sh used to be huge, and is now only 3 lines? (Which is great btw)

I have some guessed but would be good to see this confirmed.

[mfeurer]

The script was huge because it performed flake8 on the difference between the latest commit and the common ancestor between the current branch and the development branch. These differences had to be fetched and assembled. Now the script simply checks everything.