python 時間戳、時間字符串、時間對象以及時間加減處理

import time
import datetime


# 時間字符串加8小時
timestring = "2019-12-21 10:22:56"
# 轉為時間戳
timestamp = time.mktime(time.strptime(timestring, '%Y-%m-%d %H:%M:%S'))
print timestamp  # 1576894976.0

datetime_struct = datetime.datetime.fromtimestamp(timestamp)
print type(datetime_struct)  # <type 'datetime.datetime'>

datetime_obj = (datetime_struct + datetime.timedelta(hours=8))
print datetime_obj  # 2019-12-21 18:22:56  <type 'datetime.datetime'>

datetime_str = datetime_obj.strftime('%Y-%m-%d %H:%M:%S')
print datetime_str  # 2019-12-21 18:22:56  <type 'str'>