public function operatorAuthor(Query $query, TokenInterface $token)
    {
        $value = explode(',', $token->value());

        if (!empty($value)) {
            $conjunction = $token->negated() ? 'NOT IN' : 'IN';
            $subQuery = TableRegistry::get('User.Users')->find()
                ->select(['id'])
                ->where(["Users.username {$conjunction}" => $value]);

            if ($token->where() === 'or') {
                $query->orWhere(['Contents.created_by IN' => $subQuery]);
            } elseif ($token->where() === 'and') {
                $query->andWhere(['Contents.created_by IN' => $subQuery]);
            } else {
                $query->where(['Contents.created_by IN' => $subQuery]);
            }
        }

        return $query;
    }