code: def _retrieve(self):
          
          url = "%s://%s:%d/manager/status" % (self._proto, self._host, self._port)
          params = {}
          params['XML'] = 'true'
          response = util.get_url(url, self._user, self._password, params)
          tree = ElementTree.XML(response)
          return tree
docs: Query Apache Tomcat Server Status Page in XML format and return 
          the result as an ElementTree object.
          
          @return: ElementTree object of Status Page XML.