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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 _is_dst(dt):
 """ Returns True if a given datetime object represents a time with DST shift. """

        # we can't use `dt.timestamp()` here since it requires a `utcoffset`
        # and we don't want to get into a recursive loop
        localtime = time.localtime(time.mktime((
            dt.year,
            dt.month,
            dt.day,
            dt.hour,
            dt.minute,
            dt.second,
            dt.weekday(),
            0,              # day of the year
            -1              # dst
        )))
        return localtime.tm_isdst > 0