def time_slot(hour):
    """
    Receives an hour as parameter
    Divides the day in 6 times 4 hour slots
    Returns the 4 hour time slot in which the given hour belongs to
    """
    slot = list(range(0, 28, 4))
    for i in range(len(slot)-1):
        if hour <= slot[i+1]:
            return (slot[i], slot[i+1])