如何用python讀取csv表格中的時間列，並進行時間最大值和最小值的相減？求代碼。。。

import?csv

import?datetime

with?open('site_info.csv','r')?as?csvfile:

reader?=?csv.reader(csvfile)

mod_times?=?[row[-1]?for?row?in?reader]

mod_times?=?[datetime.datetime.strptime(x,?r"%Y/%m/%d?%H:%M")?for?x?in?mod_times[1:]]

max_time?=?max(mod_times)

min_time?=?min(mod_times)

diff_day?=?(max_time?-?min_time).days

diff_sec?=?(max_time?-?min_time).seconds

m,?s?=?divmod(diff_sec,?60)

h,?m?=?divmod(m,?60)

print?"%d?days,%02d?hours,%02d?minites,%02d?seconds"?%(diff_day,h,?m,?s)