I spent a few hours cleaning up a really old Python library, ProxyTypes. Two days from now will mark 10 years since it was updated. Today, I updated it to support the newer Python 3, and to be compliant with the PEP8 style guide. I've stripped out some of the code I don't need, but the functionality and logic of the remaining code are unchanged.
I want to redistribute my modified version with a larger software project of mine, omitting all setup files and only including my modified version of the core file. My project is MIT licensed.
I've tried reading the PSF license text, but the license seems to talk specifically about redistribution of Python itself, and
ProxyTypes is a 3rd-party module which is not distributed with Python, as far as I can tell, so I quickly became confused as to which parts of the PSF license actually apply to the code I'm trying to redistribute.
Additionally, it appears that the PSF license has changed dramatically over time. This code is 10 years old, should I assume that the PSF license means whatever version was current at the time of publication?
What attribution do I need to include my modified version of this file? Should I include my own copyright below any other necessary attribution to show that I've modified it, not merely redistributed it?