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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def tzname(self, dt):
 """datetime -> string name of time zone."""

        tt = _localtime(_mktime((dt.year, dt.month, dt.day,
                 dt.hour, dt.minute, dt.second, dt.weekday(), 0, -1)))
        return _time.tzname[tt.tm_isdst > 0]