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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 retract(self, jid, node, id_, *, notify=False):
 """ Retract a previously published item from a node. :param jid: Address of the PubSub service. :type jid: :class:`aioxmpp.JID` :param node: Name of the PubSub node to send a notify from. :type node: :class:`str` :param id_: The ID of the item to retract. :type id_: :class:`str` :param notify: Flag indicating whether subscribers shall be notified about the retraction. :type notify: :class:`bool` :raises aioxmpp.errors.XMPPError: as returned by the service Retract an item previously published to `node` at `jid`. `id_` must be the ItemID of the item to retract. If `notify` is set to true, notifications will be generated (by setting the `notify` attribute on the retraction request). """

        retract = pubsub_xso.Retract()
        retract.node = node
        item = pubsub_xso.Item()
        item.id_ = id_
        retract.item = item
        retract.notify = notify

        iq = aioxmpp.stanza.IQ(to=jid, type_=aioxmpp.structs.IQType.SET)
        iq.payload = pubsub_xso.Request(
            retract
        )

        yield from self.client.send(iq)