Hint	Means
`list[int]`	a list of ints
`dict[str, float]`	a dictionary from strings to floats
`tuple[int, int]`	a pair of ints
`set[str]`	a set of strings
`int \| None`	an int, or None
`int \| str`	an int or a string

def average(marks: list[int]) -> float:
    return sum(marks) / len(marks)

def find(names: list[str], target: str) -> int | None:
    for i, n in enumerate(names):
        if n == target:
            return i
    return None

prices: dict[str, float] = {"tea": 1.8}
print(average([70, 80]), find(["a", "b"], "b"), find([], "z"))

int | None is the honest hint for a function that might not find anything. It reminds callers to handle the None case.