Yes - but as I said, you can be confident that the list type is accurate, and if you want to convert that list to a specific-length list type then you're nudged towards doing it in a way where you handle the case where the list isn't actually the length you specified.

> And by the List[str] bit, I mean you can annotate it as doing whatever it in fact does. You aren’t protected if you get that wrong, of course

Not "of course"; the whole point of a type system is that it's automatically checked and therefore you can have reasonable confidence in the types you're given.