Python Typing Patterns Modern type hints for safe, documented Python code. Basic Annotations Collections Optional and Union TypedDict Callable Generics Protocol (Structural Typing) Type Guards Literal and Final Quick Reference | Type | Use Case | |------|----------| | | Optional value | | | Homogeneous list | | | Dictionary | | | Function type | | | Generic parameter | | | Structural typing | | | Dict with fixed keys | | | Specific values only | | | Cannot be reassigned | Type Checker Commands Emerging: — Astral's Rust-based type checker (same toolchain as uv + ruff), dramatically faster than…