Hi, I'm a PSF Director and the PSF's Treasure as of this year. For transparency, our tax returns as of 2018 (and soon 2019) are up on https://www.python.org/psf/records/
You are right that this donation does not show up in our tax filings because they provide it to any OSS project.
You are right that this donation does not show up in our tax filings because they provide it to any OSS project.