REF: move safe_sort to algos to avoid private/circular dependencies

[jbrockmendel]

safe_sort uses private functions from core.algorithms and is runtime-imported into core.algorithms. It also doesn't use anything else defined in core.sorting. This move cleans up the dependency structure, in particular is a step towards getting #29133 working.

[jreback]

rather than adding to algos i would put in a separate module
maybe let’s create

pandas/corr/algos/sorting.py, safe_sort.py, algos.py

[jbrockmendel]

pandas/corr/algos

I think we're going to get there before long, yah. There are a few parts of algorithms.py that are inextricably intertwined with Series, but a bunch of it can be made low-dependency with a few tweaks. One of those tweaks is going to be inside safe_sort, which still has a runtime import of Index which I plan to address in the next step. After that is when I was thinking of making core/algos/ a directory

[jreback]

right but rather than moving it twice wouldn’t make sense to move to safe_sort.py now?

[jbrockmendel]

either way i guess. making a new directory and moving a bunch of stuff into it entails updating a lot of other imports

[jreback]

since this is a moving PR, I think doing it here is better (e.g. just move this for now to pandas/core/algos/safe_sort.py), then changing other things can be a follow on

[jbrockmendel]

since this is a moving PR, I think doing it here is bette

last effort to push back before i go along with this: safe_sort uses private functions from algorithms.py, moving just safe_sort without carefully handling the rest of the module doesn't improve things on that front

[jreback]

since this is a moving PR, I think doing it here is bette

last effort to push back before i go along with this: safe_sort uses private functions from algorithms.py, moving just safe_sort without carefully handling the rest of the module doesn't improve things on that front

ok fine..... but would love the refactor - ok on doing as followons