import datetime

 

d = datetime.datetime.now()

 

def day_get(d):

    oneday = datetime.timedelta(days=1)

    day = d - oneday

    date_from = datetime.datetime(day.year, day.month, day.day, 0, 0, 0)

    date_to = datetime.datetime(day.year, day.month, day.day, 23, 59, 59)

    print '---'.join([str(date_from), str(date_to)])

 

def week_get(d):

    dayscount = datetime.timedelta(days=d.isoweekday())

    dayto = d - dayscount

    sixdays = datetime.timedelta(days=6)

    dayfrom = dayto - sixdays

    date_from = datetime.datetime(dayfrom.year, dayfrom.month, dayfrom.day, 0, 0, 0)

    date_to = datetime.datetime(dayto.year, dayto.month, dayto.day, 23, 59, 59)

    print '---'.join([str(date_from), str(date_to)])

 

def month_get(d):

    dayscount = datetime.timedelta(days=d.day)

    dayto = d - dayscount

    date_from = datetime.datetime(dayto.year, dayto.month, 1, 0, 0, 0)

    date_to = datetime.datetime(dayto.year, dayto.month, dayto.day, 23, 59, 59)

    print '---'.join([str(date_from), str(date_to)])




转载自http://www.oschina.net/code/snippet_736230_26816