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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_node_config(self, jid, config, node=None):
 """ Update the configuration of a node. :param jid: Address of the PubSub service. :type jid: :class:`aioxmpp.JID` :param config: Configuration form :type config: :class:`aioxmpp.forms.Data` :param node: Name of the PubSub node to query. :type node: :class:`str` :raises aioxmpp.errors.XMPPError: as returned by the service :return: The configuration of the node. :rtype: :class:`~.forms.Data` .. seealso:: :class:`aioxmpp.pubsub.NodeConfigForm` """


        iq = aioxmpp.stanza.IQ(to=jid, type_=aioxmpp.structs.IQType.SET)
        iq.payload = pubsub_xso.OwnerRequest(
            pubsub_xso.OwnerConfigure(node=node)
        )
        iq.payload.payload.data = config

        yield from self.client.send(iq)