def METHOD_NAME(identifier, filing_id, comment_id=None):
    """Return a JSON object with meta information about the Service."""
    # basic checks
    err_msg, err_code = _basic_checks(identifier, filing_id, request)
    if err_msg:
        return jsonify(err_msg), err_code
    comments = db.session.query(Comment).filter(Comment.filing_id == filing_id)
    if comment_id:
        comment = comments.filter(Comment.id == comment_id).one_or_none()
        if not comment:
            return jsonify({'message': f'Comment {comment_id} not found'}), HTTPStatus.NOT_FOUND
        return jsonify(comment.json)
    rv = []
    for comment in comments:
        rv.append(comment.json)
    return jsonify(comments=rv)