For some time now, Python has had the ability to “annotate” names with type information, in one form or another. With Python 3.5, type hints officially became part of the language (PEP 484).

Mypy, Pytype, Pyright, and Pyre can help you keep your type-hinted Python code bug-free. Let’s see what each of these useful tools has to offer. In the beginning, Python had no type decorations.