@staticmethod
def _test_range(weekday, hours, minutes, seconds):
    """Test if values are in the correct value range."""
    if weekday < 0 or weekday > 7:
        return False
    if hours < 0 or hours > 23:
        return False
    if minutes < 0 or minutes > 59:
        return False
    if seconds < 0 or seconds > 59:
        return False
    return True
