Documentation
The docs for bisect.bisect use a kind of funky pattern with a list as a default argument:
https://docs.python.org/3/library/bisect.html#examples
Using a list as a default argument is a really common pattern beginners think will be helpful but usually isn't due to the way default arguments are bound to the class object instead of instances. It's also distracting for more advanced readers who are trained to spot this pattern in code reviews.
IMO this example would be clearer if grade accepted no arguments besides score and the defaults were inlined.
Linked PRs