Libraries are collections of shared code. They're common in Python, where they're also called "modules," but they're also ...

I've grabbed Sequence from the typing module, which includes all three Python sequence types—strings, lists and tuples. Once I do that, all of the mypy problems disappear, because all of the arguments ...

Now, type hinting and the typing module are supported directly by the Python interpreter. Type hints in Python aren’t enforced at runtime.