public static function addNewUser($username, $firstName, $lastName, $email, $password)
 {
     $selector = new DBSelect('localhost', 'root', '', 'mydb');
     $result = $selector->hasUserUsername($username);
     if ($result) {
         $selector = null;
         return false;
     } else {
         $selector = null;
         $insertor = new DBInsert('localhost', 'root', '', 'mydb');
         $insertor->insertNewUser($username, $firstName, $lastName, $email, $password);
         $insertor = null;
         return true;
     }
 }