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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 get_stream(self, channel):
 """Return the stream of the given channel :param channel: the channel that is broadcasting. Either name or models.Channel instance :type channel: :class:`str` | :class:`models.Channel` :returns: the stream or None, if the channel is offline :rtype: :class:`models.Stream` | None :raises: None """

        if isinstance(channel, models.Channel):
            channel = channel.name

        r = self.kraken_request('GET', 'streams/' + channel)
        return models.Stream.wrap_get_stream(r)