datatime模块

import datetime
print(datetime.datetime.today())#获取当前时间，到秒 2018-07-31 21:44:54.316039
print(datetime.datetime.now())#获取当前时间，到秒,同上 2018-07-31 21:44:54.316039

print(datetime.datetime.today().strftime('%S'))#指定格式,格式化时间 54
print(datetime.datetime.today()+datetime.timedelta(-3))#三天前时间 2018-07-28 21:44:54.316039
print(datetime.date.today())#取当天的日期，只是日期 2018-07-31
print(datetime.datetime(2018,1,19,15,13))#2018-01-19 15:13:00