Levels of Python type annotations

Python has optional type annotations - also called "type hints". Like this: def entry_to_dict ( entry : Entry ) -> dict : return { ' title ' : entry . title , ' num_likes ' : entry . num_likes , ' url ' : entry . url , } The annotations here being "Entry" as the type for the "entry" argument, and "dict" as the return type. In fact, there are at least 3 ways type annotations can be used: documentation to configure libraries and tools static type checking These are so different, asking "do you use