TYPO3 extbase Cache Manager injection

cacheManager.php

    /**
     * cacheManager
     *
     * @var \TYPO3\CMS\Core\Cache\CacheManager
     * @inject
     */
    protected $cacheManager;
    
//     if (($result = $this->cacheManager->getCache('extension_key')->get('cacheKey')) === false) {
//         $query  = $this->createQuery();
//         $result = $query->execute();
//         $this->cacheManager->getCache('extension_key')->set('cacheKey', $result, [], 3600);
//     }
//     return $result;