> I've gone and made a patch for this change

Update:

* The preparatory changes in #37760 are now almost all merged; GH-15265 is the one piece remaining, and I'd be grateful for a review.

It's a generally straightforward and boring change that converts the main data structures of makeunicodedata.py from using length-18 tuples as records to using a dataclass, which I think makes subsequent changes that add features to that script much easier both to write and to review.

* I have a slightly updated version of the fix itself, which differs mainly by adding a test: https://github.com/gnprice/cpython/commit/9b3bf6739 Comments welcome there too.