looking fo documentation for module files

[Gribouillis]

So one advantage that this work all python version as OS environment variable control this.

This is also the greatest flaw of PYTHONPATH. Using the same installed modules for several versions of Python leads to troubles and inconsistencies.

The only case where I use PYTHONPATH is for altering temporarily the environment when I launch a command in the Linux terminal or in a Bash script, for exemple

Output:
$ PYTHONPATH="/some/dir" python spam.py

I don't know if Windows' command line supports this kind of invocation.