def is_leap(year: int) -> bool:
    """Returns True if year is a leap year
    :param:
        year: Represents a year
    :returns:
        bool: True if year is a leap year
    """

    # Leap years are years that are divisible by 4, and not by 100 OR are divisible by 400!
    CASE1: bool = year % 4 == 0
    CASE2: bool = year % 100 == 0
    CASE3: bool = year % 400 == 0

    return CASE1 and not CASE2 or CASE3