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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 set_nick(self, new_nick):
 """ Change the nick name of the occupant. :param new_nick: New nickname to use :type new_nick: :class:`str` This sends the request to change the nickname and waits for the request to be sent over the stream. The nick change may or may not happen, or the service may modify the nickname; observe the :meth:`on_nick_change` event. .. seealso:: :meth:`.AbstractConversation.set_nick` for the full interface specification. """


        stanza = aioxmpp.Presence(
            type_=aioxmpp.PresenceType.AVAILABLE,
            to=self._mucjid.replace(resource=new_nick),
        )
        yield from self._service.client.send(
            stanza
        )