Basically ok. However, I'm not a fan of using 'Cn' in cases that do not relate to a color sequence. Instead, we should use the color names 'tab:blue' etc instead. I've noted this down for one example but there are more similar cases in here.

Agree with @timhoffm 's comments. 👍 on merging with those changes.

flake8 complains:

./examples/pyplots/pyplot_two_subplots.py:0:1: X100 Superfluous per-file-ignores for E302

Can be merged after that's fixed.