> How about keeping a substitute or mapped drive from the input path
> if resolving the root path on the drive prefixes the overall real
> path? That would be pretty easy to implement.

So if the resolved path is accessible from the original path's drive, then keep the drive?
This is what 'realpath' in Ruby does. Good idea, in my opinion.
Letting this be default behavior (controlled by keyword argument) would prevent the issues with mounted drives.

> For your own needs, you could add a sitecustomize.py file that
> does "ntpath.realpath = ntpath.abspath". That will change the
> behaviour back to what it was in 3.7.

It works. Thank you very much.

-----

Since you provided the working solution for me, the destiny of this bug report is at your discretion.