Python time datetime常用时间处理方法

import datetime
# 获取当前时间
d1 = datetime.datetime.now()
print d1
# 当前时间加上半小时
d2 = d1 + datetime.timedelta(hours=0.5)
print d2
# 格式化字符串输出
d3 = d2.strftime('%Y-%m-%d %H:%M:%S')
print d3
# 将字符串转化为时间类型
d4 = datetime.datetime.strptime(date,'%Y-%m-%d %H:%M:%S.%f')
print d4

# -*- coding:utf-8 -*-
import datetime
def first_day_of_month():
'''
获取本月第一天
:return:
'''
# now_date = datetime.datetime.now()
# return (now_date + datetime.timedelta(days=-now_date.day + 1)).replace(hour=0, minute=0, second=0,
# microsecond=0)
return datetime.date.today() - datetime.timedelta(days=datetime.datetime.now().day - 1)
def first_day_of_week():
'''
获取本周第一天
:return:
'''
return datetime.date.today() - datetime.timedelta(days=datetime.date.today().weekday())
if __name__ == "__main__":
this_week = first_day_of_week()
last_week = this_week - datetime.timedelta(days=7)
this_month = first_day_of_month()
last_month = this_month - datetime.timedelta(days=(this_month - datetime.timedelta(days=1)).day)
print this_week
print last_week
print this_month
print last_month