private static function referentTracker($keywords, $referents)
 {
     $match = [];
     foreach ($referents as $key => $referent) {
         $lastTweets = Twitter::getUserTimeline(['screen_name' => $referent->account, 'count' => 100, 'format' => 'json']);
         $keyfound = Self::keywordFinder($lastTweets, $keywords);
         array_push($match, $keyfound);
     }
     return $match;
 }