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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 dehydrate_datetime(value):
 """ Dehydrator for `datetime` values. :param value: :type value: datetime :return: """


    def seconds_and_nanoseconds(dt):
        if isinstance(dt, datetime):
            dt = DateTime.from_native(dt)
        zone_epoch = DateTime(1970, 1, 1, tzinfo=dt.tzinfo)
        t = dt.to_clock_time() - zone_epoch.to_clock_time()
        return t.seconds, t.nanoseconds

    tz = value.tzinfo
    if tz is None:
        # without time zone
        value = utc.localize(value)
        seconds, nanoseconds = seconds_and_nanoseconds(value)
        return Structure(b"d", seconds, nanoseconds)
    elif hasattr(tz, "zone") and tz.zone:
        # with named time zone
        seconds, nanoseconds = seconds_and_nanoseconds(value)
        return Structure(b"f", seconds, nanoseconds, tz.zone)
    else:
        # with time offset
        seconds, nanoseconds = seconds_and_nanoseconds(value)
        return Structure(b"F", seconds, nanoseconds, tz.utcoffset(value).seconds)