将TimeDiff转换为总秒数
问题描述：
我有时差
time1 = datetime.datetime.fromtimestamp(time.mktime(time.gmtime()))
...
time2 = datetime.datetime.fromtimestamp(time.mktime(time.gmtime()))
diff = time2 - time1
现在，如何找到通过的总秒数？ diff.seconds 不计算天数。我可以做：
Now, how do I find the total number of seconds that passed? diff.seconds doesn't count days. I could do:
diff.seconds + diff.days * 24 * 3600
是否有内置方法？