python 计算两个日期之间相隔的月数：
>>> from dateutil import rrule >>> import datetime >>> from dateutil import rrule >>> d1 = datetime.date(2010,8,30) >>> d2 = datetime.date(2011,5,3) >>> months = rrule.rrule(rrule.MONTHLY, dtstart=d1, until=d2).count() >>> months 8