'Delete a single item from a node.'

def retract(self, jid, node, id, notify=None, ifrom=None, block=True, callback=None, timeout=None):

    iq = self.xmpp.Iq(sto=jid, sfrom=ifrom, stype='set')
    iq['pubsub']['retract']['node'] = node
    iq['pubsub']['retract']['notify'] = notify
    iq['pubsub']['retract']['item']['id'] = id
    return iq.send(block=block, callback=callback, timeout=timeout)
