Alaouy\Youtube\Youtube::getPlaylistItemsByPlaylistId PHP Method

    public function getPlaylistItemsByPlaylistId($playlistId, $pageToken = '', $maxResults = 50, $part = ['id', 'snippet', 'contentDetails', 'status'])
    {
        $API_URL = $this->getApi('playlistItems.list');
        $params = array('playlistId' => $playlistId, 'part' => implode(', ', $part), 'maxResults' => $maxResults);
        // Pass page token if it is given, an empty string won't change the api response
        $params['pageToken'] = $pageToken;
        $apiData = $this->api_get($API_URL, $params);
        $result = ['results' => $this->decodeList($apiData)];
        $result['info']['nextPageToken'] = isset($this->page_info['nextPageToken']) ? $this->page_info['nextPageToken'] : false;
        $result['info']['prevPageToken'] = isset($this->page_info['prevPageToken']) ? $this->page_info['prevPageToken'] : false;
        return $result;
    }

 public function testGetPlaylistItemsByPlaylistId()
 {
     $GOOGLE_ZEITGEIST_PLAYLIST = 'PL590L5WQmH8fJ54F369BLDSqIwcs-TCfs';
     $response = $this->youtube->getPlaylistItemsByPlaylistId($GOOGLE_ZEITGEIST_PLAYLIST);
     $data = $response['results'];
     $this->assertTrue(count($data) > 0);
     $this->assertEquals('youtube#playlistItem', $data[0]->kind);
 }