def is_leap_year(year: int) -> bool:
    """
    Determine whether a given year is a leap year.

    Rules
    -----
    A year is a leap year when it is divisible by 4, except for century
    years (divisible by 100), which are leap years only when they are also
    divisible by 400.

    So 2024 is a leap year, 1900 is not, and 2000 is.

    Parameters
    ----------
    year : int
        The year to check.

    Returns
    -------
    bool
        True if the year is a leap year, False otherwise.

    Examples
    --------
    >>> is_leap_year(2024)
    True
    >>> is_leap_year(2023)
    False
    >>> is_leap_year(1900)
    False
    >>> is_leap_year(2000)
    True
    """
    raise NotImplementedError("Replace this line with your code.")