CLN: move maybe_casted_values from pandas/core/frame.py to pandas/core/dtype/cast.py
- [ ] closes #xxxx
- [ ] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

xref #36876, #27370 (stale PR)
For something thats only used once, im not sure it is worth moving.  Definitely worth seeing if this can be simplified though, per a couple of TODO comments in there > Definitely worth seeing if this can be simplified though, per a couple of TODO comments in there

@jbrockmendel Will do! (in a followon) ping on green-ish (meaning either green or a specific buidl is failing on completely unrelated; though I think @jbrockmendel may have fixed this). thanks @arw2019 

if you can rebase the typing one on master would be great. > thanks @arw2019

Thanks @jreback @jbrockmendel for reviewing!

> if you can rebase the typing one on master would be great.

Done