python获取当前时间的前一天，前一周，前一个月。，python当前时间,datetime.tim

python获取当前时间的前一天，前一周，前一个月。，python当前时间,datetime.tim

datetime.timedelta的使用来避免跨年跨月的问题

import datetimed = 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)])#该片段来自于http://byrx.net