The familiar formatted string, or f-string, feature in Python provides a convenient way to print variables as part of a string. But it doesn’t let you interact with the way strings are created ...

For instance, binary operations (add, subtract, etc.) can be replaced with specialized versions for integers, floats, and strings. Python function calls also require less overhead in Python 3.11.

I don't want to dwell on how all of this works, including inner functions and Python's scoping rules. I do, however, want to ask the question "how can you use Mypy to check all of this?" You could ...

Not sure about rational support, but SmallTalk and ABC (predecessor to Python) have 'exact' or something, at least for integers, so you can do silly things like 1000!, if you have enough memory ...