def parse_period(period):
    """
    Parse a 'period' out to it's two parts

    >>> parse_period('minute-15')
    ('minute', 15)
    >>> parse_period('day')
    ('day', 1)
    """
    unit = period.split('-')[0]
    quantity = int((period.split('-') + ['1'])[1])
    return (unit, quantity)