def test_formatTimeDefault(self):
        """
        Time is first field.  Default time stamp format is RFC 3339 and offset
        respects the timezone as set by the standard C{TZ} environment variable
        and L{tzset} API.
        """
        if tzset is None:
            raise SkipTest(
                "Platform cannot change timezone; unable to verify offsets."
            )

        addTZCleanup(self)
        setTZ("UTC+00")

        t = mktime((2013, 9, 24, 11, 40, 47, 1, 267, 1))
        event = dict(log_format=u"XYZZY", log_time=t)
        self.assertEqual(
            formatEventAsClassicLogText(event),
            u"2013-09-24T11:40:47+0000 [-\x23-] XYZZY\n",
        )

        Time is first field.  Default time stamp format is RFC 3339 and offset
        respects the timezone as set by the standard C{TZ} environment variable
        and L{tzset} API.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/logger/test/test_format.py