Python's os.path.realpath, when used with a substed drive on the Windows platform, don't resolve the substed path to the *real* path. 

For example creating a substed drive like this:

    subst z: C:\Users\Public\Desktop

and checking for the real path in python like this:

    import os
    myPath = "S:\\"
    print("Real path of: " + myPath + " is: " + os.path.realpath(myPath) )

prints

    Real path of: S:\ is: S:\

In the docs for the [subst][1] command, a substed drive is referred to as a *virtual* drive. Virtual, suggesting something being "not real", indicates that the Python *realpath* command is not working properly on Windows. 


  [1]: https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/subst

In Windows, realpath is currently an alias for abspath. Issue 14094 has a pending PR that implements realpath, but it's waiting on improved tests and final approval. I'm afraid it won't make it into 3.8.

I suggest using the resolve() method of a pathlib.Path. For example:

    >>> os.system('subst W: C:\\Windows')
    0
    >>> pathlib.Path('W:\\').resolve()
    WindowsPath('C:/Windows')