Track 12 · Lesson 8 of 12

Type hints in depth

Describe data precisely with modern type hints — unions, None, nested collections, Callable, TypedDict, Protocol and generics — and know what hints do and don't do at runtime.

You will be able to

• Annotate functions with unions, X | None, nested collection types and Callable
• Describe dictionary records with TypedDict and duck-typed interfaces with Protocol
• Write generic functions and classes with the PEP 695 [T] syntax
• Explain that hints are not checked when the program runs, and validate untrusted input yourself