Backport PR #48890 on branch 1.5.x (ERR: Improve error message when assigning a complete row using 'at' m…)

[meeseeksmachine]

Backport PR #48890: ERR: Improve error message when assigning a complete row using 'at' m…

[phofl]

cc @ambujpawar This fails on the backport. Could you check?

Edit: Sorry forget it, this is a more general issue

[ambujpawar]

Hi, just glanced through the error messages. The error doesnt seem to be in running this command:
xvfb-run pytest -r fEs -n auto --dist=loadfile -s --cov=pandas --cov-report=xml --cov-append pandas -m "not slow and not network and not single_cpu"

And the error message seems to be:
INTERNALERROR> ModuleNotFoundError: No module named 'py.log'; 'py' is not a package

I have not seen this before(and doesnt seem much related to the #48890 ), maybe you guys might have seen it before and have some tips on how to solve it?

Otherwise, I will just look more into it during the evening :)