This is an example where the pre-commit hook catches something that flake8 does not. It would be nice if they were consistent. @kolibril13 this needs some whitespace fixes....

@jklymak Flake8 will never get this error, as flake8 is only about python source files.
Each pre-commit hook can be configured to run on specific files (the trailing whitespace one runs on all text files except SVGs)

This particular trailing whitespace is in a README.txt.

If it were in python source, it would be W291 (from pycodestyle), which is selected by our flake8 config.

Owee, I'm MrMeeseeks, Look at me.

There seem to be a conflict, please backport manually. Here are approximate instructions:

1. Checkout backport branch and update it.

git checkout v3.7.x
git pull

2. Cherry pick the first parent branch of the this PR on top of the older branch:

git cherry-pick -x -m1 91d8f2e882bf6fc441276c64590a54d659f2c8a4

3. You will likely have some merge/cherry-pick conflict here, fix them and commit:

git commit -am 'Backport PR #25157: Small tweak in chapter sorting of the example gallery'

4. Push to a named branch:

git push YOURFORK v3.7.x:auto-backport-of-pr-25157-on-v3.7.x

5. Create a PR against branch v3.7.x, I would have named this PR:

"Backport PR #25157 on branch v3.7.x (Small tweak in chapter sorting of the example gallery)"

And apply the correct labels and milestones.

Congratulations — you did some good work! Hopefully your backport PR will be tested by the continuous integration and merged soon!

Remember to remove the Still Needs Manual Backport label once the PR gets merged.

If these instructions are inaccurate, feel free to suggest an improvement.

Even though it is a documentation change, I'm going to err on the side of not backporting.