# -*- coding: utf-8 -*-from  datetime import datetimeimport time# 取当前时间，返回string类型now_str = time.strftime("%Y-%m-%d %H:%M:%S") print (type(now_str))    print now_strprint ‘---‘# 取当前时间,返回datetime类型print (type(datetime.now()))    print datetime.now()print ‘---‘# string -> datetimetime_type = datetime.strptime(now_str, "%Y-%m-%d %H:%M:%S") print type(time_type)print time_typeprint ‘---‘# datetime -> stringstr_type = datetime.strftime(time_type, "%Y-%m-%d %H:%M:%S") print type(str_type)print str_type#计算时间间隔starttime = datetime.now()endtime = datetime.now()print (endtime - starttime).seconds# 构造datetime对象new_dt = datetime(2005, 2, 16)print type(new_dt)print new_dt# 日期计算,这里需要datetime，而不是datetime.datetimeyesterday_date = datetime.datetime.now() - datetime.timedelta(days=1)  yesterday_str = datetime.datetime.strftime(yesterday_date, "%Y%m%d")# datetime to timestampimport timeint(time.mktime(dt.timetuple()))# timestamp to datetimedt = datetime.fromtimestamp(timestamp)