def test_retract(self):
        xml = """
        <iq type='set' to='pubsub.example.org'
                       from='user@example.org'>
          <pubsub xmlns='http://jabber.org/protocol/pubsub'>
            <retract node='test'>
              <item id='item1'/>
              <item id='item2'/>
            </retract>
          </pubsub>
        </iq>
        """

        def cb(result):
            self.assertEquals('feature-not-implemented', result.condition)
            self.assertEquals('unsupported', result.appCondition.name)
            self.assertEquals(NS_PUBSUB_ERRORS, result.appCondition.uri)
            self.assertEquals('retract-items', result.appCondition['feature'])

        d = self.handleRequest(xml)
        self.assertFailure(d, error.StanzaError)
        d.addCallback(cb)
        return d
Non-overridden L{PubSubService.retract} yields unsupported error.
dataset/ETHPy150Open ralphm/wokkel/wokkel/test/test_pubsub.py/PubSubServiceWithoutResourceTest.test_retract