python 时间差的计算
import time import datetime start = datetime.datetime.now() time.sleep(30) end = datetime.datetime.now() print (end-start).days # 0 天数 print (end-start).total_seconds() # 30.029522 精确秒数 print (end-start).seconds # 30 秒数 print (end-start).microseconds # 29522 毫秒数 import datetime now = datetime.datetime.now() three_days_ago = now + datetime.timedelta(days=-3) three_weeks_ago = now + datetime.timedelta(weeks=-3) print now # datetime.datetime(2016, 12, 22, 11, 24, 49, 987171) print three_days_ago # datetime.datetime(2016, 12, 19, 11, 24, 49, 987171) print three_weeks_ago # datetime.datetime(2016, 12, 1, 11, 24, 49, 987171)
