Python 3.5 gave us options to write asynchronous functions; Python 3.6 bolsters ... The one place where these changes break compatibility is with anything that works directly with Python bytecode.

As of Python 3.12, the GC runs only on the “eval breaker” mechanism in the Python bytecode loop—that is, between executing one bytecode and another. It also runs whenever CPython’s signal ...

It’s not executing or running any Python. This is someone’s clever custom ISA and there is no python bytecode anymore once the actual program executes.