public function parseXml($response)
    {
        parent::parseXml($response);
        $listTopicsResultXml = new \SimpleXMLElement($response);
        $this->_topicInfos = [];
        foreach ($listTopicsResultXml->entry as $entry) {
            $topicInfo = new TopicInfo();
            $topicInfo->parseXml($entry->asXML());
            $this->_topicInfos[] = $topicInfo;
        }
    }