nostr:npub1uxeg43jh6xrmyaqfatuaut4s6thj8fgw4qfvw2409qkkuxudhgks08qwlz ended up installing latest Raspberry OS on a brand new memory card and copying the Python code over from the old card, which was failing but still readable.

then, to be on the safe side, i cloned this card to another card as a backup, since he had two brand new ones, and tested that both cards were booting and running the software.

it took 3 hours to fix.