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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 unsubscribe(self, jid, node=None, *, subscription_jid=None, subid=None):
 """ Unsubscribe from a node. :param jid: Address of the PubSub service. :type jid: :class:`aioxmpp.JID` :param node: Name of the PubSub node to unsubscribe from. :type node: :class:`str` :param subscription_jid: The address to subscribe from the service. :type subscription_jid: :class:`aioxmpp.JID` :param subid: Unique ID of the subscription to remove. :type subid: :class:`str` :raises aioxmpp.errors.XMPPError: as returned by the service By default, the unsubscribe request will be for the bare JID of the client. It can be specified explicitly using the `subscription_jid` argument. If available, the `subid` should also be specified. If an error occurs, the corresponding :class:`~.errors.XMPPError` is raised. """


        subscription_jid = subscription_jid or self.client.local_jid.bare()

        iq = aioxmpp.stanza.IQ(to=jid, type_=aioxmpp.structs.IQType.SET)
        iq.payload = pubsub_xso.Request(
            pubsub_xso.Unsubscribe(subscription_jid, node=node, subid=subid)
        )

        yield from self.client.send(iq)