搜了一堆缺了time转datetime，这里放上代码：
time -> datetime
datetime.fromtimestamp(time.time())
别把time转换为localtime
datetime -> time
time.mktime(dateTim.timetuple())
time -> string
str = time.strftime("%Y-%m-%d %H:%M:%S",fileModifyTime)
string -> time
time.mktime(time.strptime(st, "%Y-%m-%d %H:%M:%S"))
datetime -> string
datetime.strftime("%Y-%m-%d %H:%M:%S")
string -> datetime
datetime.strptime(str,"%Y-%m-%d %H:%M:%S")
