#coding=utf-8
import time
import datetime

def yes_time():
    #獲取當前時間
    now_time = datetime.datetime.now()
    #當前時間減去一天 獲得昨天當前時間
    yes_time = now_time + datetime.timedelta(days=-1)
    #格式化輸出
    yes_time_str = yes_time.strftime('%Y-%m-%d %H:%M:%S')
    print yes_time_str  # 2017-11-01 22:56:02

def dif_time():
    #計算兩個時間之間差值
    now_time = datetime.datetime.now()
    now_time = now_time.strftime('%Y-%m-%d %H:%M:%S')
    d1 = datetime.datetime.strptime('2017-10-16 19:21:22', '%Y-%m-%d %H:%M:%S')
    d2 = datetime.datetime.strptime(now_time, '%Y-%m-%d %H:%M:%S')
    #間隔天數
    day = (d2 - d1).days
    #間隔秒數
    second = (d2 - d1).seconds
    print day   #17
    print second  #13475  注意這樣計算出的秒數只有小時之後的計算額 也就是不包含天之間差數

def unix_time():
    #將python的datetime轉換為unix時間戳
    dtime = datetime.datetime.now()
    un_time = time.mktime(dtime.timetuple())
    print un_time  #1509636609.0
    #將unix時間戳轉換為python  的datetime
    unix_ts = 1509636585.0
    times = datetime.datetime.fromtimestamp(unix_ts)
    print times  #2017-11-02 23:29:45