On Tue, Aug 23, 2016 at 3:39 PM, Lenjoy <mars.lenjoy@gmail.com> wrote:

summary for getting UTC time in sec:

print time.time() print calendar.timegm(time.gmtime()) print time.mktime(time.localtime()) print calendar.timegm(datetime.datetime.utcnow().timetuple()) print time.mktime(datetime.datetime.now().timetuple())

Are all the functions above expected?

Yes. The time and calendar module precede the datetime module for about a decade. If you use the datetime module, the "one obvious way" to get time in "seconds since UNIX epoch" is to call the .timestamp() method of the datetime object:

...

...

datetime.now().timestamp() # Works in Python 3.6a 1471983108.547574 datetime.now(timezone.utc).timestamp() # Faster and works since Python 3.5 1471983125.307036

Note that among the functions that you listed only the first will return fractions of a second. If you don't need the datetime module functionality and want to work with floating point (or integer) timestamps - use time.time() method to get the current time. The other functions of the time and calendar modules will come handy when you need to convert between timestamps and human-readable time formats. The datetime module was designed to operate on times directly in the human-readable form and you are not expected to need to convert datetime instances to timestamps except for interoperability with external libraries. PS: From the use of the print statement in your summary, I conclude that you still use Python 2.x. The datetime module has seen several enhancements in the 3.x series and more features are still being added.