How to run example

[PhilterPaper]

Pardon me for asking something that's probably simple, but I'm new to Python and haven't figured out yet how to run the example program. I'm trying to find a correctly-running implementation of Knuth-Plass, and want to test this library with a number of inputs before I compare against it to correct my Perl implementation (Text::KnuthPlass) that I recently took over maintenance of. It seems to have a number of problems, as does the bramstein/typeset Javascript implementation that it was derived from. I figured if I could find a working and supported implementation to work with, that could save me a lot of time and effort compared to starting from scratch with the Plass paper or Knuth's TeX book (TeX: The Program).

I am on Windows 10, running from the DOS command shell (command-line). Python 3.9.7 is installed. Thanks much to anyone who can tell me what file to run and in what manner. Everything I've tried keeps complaining

Traceback (most recent call last):
  File "C:\Users\***\Desktop\texlib-master\texlib\tests\test_wrap.py", line 4, in <module>
    from texlib import wrap
ModuleNotFoundError: No module named 'texlib'

What's it trying to tell me? Is this a directory structure problem, a permissions problem, or something else? I'm new to Python, so if it's really finicky about something, I am not aware of it. Basically, I unzipped the Github download onto the Desktop, and tried running from a number of different directories under it, both with and without an explicit "python" in the command (.py appears to be running Python). Thanks!