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Type hints
Annotations that describe expected types: `def f(x: int) -> str:`. Not enforced at runtime — used by tools like mypy.
def greet(name: str) -> None: ...
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Open lesson lesson-101 →Related — Syntax
f-stringAn f-prefixed string literal that lets you inline expressions: `f"x={x}"`. Intro…Walrus operator`:=` assigns inside an expression. Useful when you'd otherwise compute the same …Truthy / falsyValues that act as True / False in `if` statements. Empty containers, `0`, `None…SlicingSubstring/sublist via `s[start:stop:step]`. Negative indices count from the end.