Please optimize the number of git commits.
You can even do fewer commits or force push them at the end so that we only see a few commits rather than the commit army.
I believe it will make the pull request more attractive and easier to review.

Okay, so the intention here is to change test_utils.py so that we're only ever testing against public API.

There's a mix here of some tests that do that, and some other tests that correctly switch to only using public imports, but switch to using private accessors.

I could review the PR as a whole, but it's a bit of a mix.

Perhaps an easier approach to getting this resolved would be to only target one type of change at a time.

but switch to using private accessors.

previous PR like this also used private accessor, so I thought it's no problem using them in tests at all.

close in favor of separating to chunks...