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There is definitely truth to this statement. However often when I write something that’s hard to type, it’s a code smell. Ex. A complex nested map should probably be represented by a few concrete classes/abstractions.

(Similar to when you something you wrote is hard to test, it’s probably just poorly abstracted code.)

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I agree and I think a good thing about the type hints is they help uncover these kinds of code smells. But there are definitely cases where it's definitely not worth the effort to fight mypy.

One example is that variable re-assignment can cause type errors in mypy but re-assigning a variable to a value of a different type is an extremely common and reasonable thing to do in Python. Another situation where strict typing can be borderline hopeless is when parsing e.g. very dynamic content like json. Sure you could encode every possible situation using types but this would basically defeat the purpose of using Python for such a task.

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