CI, CLN remove unnecessary noqa statements, add CI check
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`

This changes loads of files, but most changes are quite trivial
LGTM > This changes loads of files, but most changes are quite trivial

Many trivial improvements is a non-trivial improvement 😄  can you rebase just to make sure Are we only down to F401 and F403? If so can we just fix the import machinery and get rid of noqa statements altogether? I think would be preferable to adding another tool to code checks Sure, have merged and pushed

@WillAyd in #36684 Jeff wrote

> ideally if we have a script to see these (maybe a grep is enough), and even better to have a code-check, but not sure how heavy handed that is.

Currently it only takes about 4-5 minutes to run all the checks we're doing in pre-commit on the entire codebase, and this one accounts for about 20 seconds.

FWIW, my suggestion would be to keep this in until the import machinery is fixed, and _then_ to remove it once there are no `noqa`s anymore > Are we only down to F401 and F403? If so can we just fix the import machinery and get rid of noqa statements altogether? I think would be preferable to adding another tool to code checks

i don't think a big deal on time; these are on the azure builds and are still faster than travis so nbd. thanks @MarcoGorelli 