python tutorial python date function example

#datetime
import datetime
#当前日期
now = datetime.datetime.now()
print(now.strftime('%Y-%m-%d %H:%M:%S'))
print(now.strftime('%Y-%m-%d'))
#string convert to datetime
time_str = '2013-07-29 09:05:00'
str_convert_2_time = datetime.datetime.strptime(time_str, '%Y-%m-%d %H:%M:%S')
print(str_convert_2_time)
#比较两个日期相差多少天
time_strA = '2013-07-29 09:05:00'
time_strB ='2013-08-29 09:05:00'
day = datetime.datetime.strptime(time_strA, '%Y-%m-%d %H:%M:%S')
day2 = datetime.datetime.strptime(time_strB, '%Y-%m-%d %H:%M:%S')
sub_day = day2 - day
print('{0}和{1}相差{2}天'.format(time_strA, time_strB, str(sub_day.days)))
#今后的n天的日期
n_days = 4
now = datetime.datetime.now()
my_date = datetime.timedelta(days=n_days) 
n_day = now + my_date
print('从今天起的{0}天的日期是：'.format(n_days))
print(n_day.strftime('%Y-%m-%d %H:%M:%S'))