Python日期时间相反

y=(datetime.datetime.now() ).strftime(\"%y%m%d\")

\'110418\'

\'2011-07-15\'

import datetime

t = datetime.datetime.today()
print type(t)

tdate =datetime.datetime.strptime(\'110416\', \'%y%m%d\') 
print type(tdate)

d =t-tdate
print d  

3 days, 15:14:38.921000

strptime

import datetime

my_date = datetime.datetime.strptime(\'2011-07-15\', \'%Y-%m-%d\')

datetime.timedelta

print d.days

import time
time.strptime(\'2011-07-15\', \'%Y-%m-%d\')