How to use the pygerrit2.rest.GerritRestAPI function in pygerrit2

pattern = re.compile(r"^([\d]+)(month[s]?|year[s]?|week[s]?)")
    match = pattern.match(options.age)
    if not match:
        logging.error("Invalid age: %s", options.age)
        return 1
    message = "Abandoning after %s %s or more of inactivity." % \
        (match.group(1), match.group(2))

    if options.digest_auth:
        auth_type = HTTPDigestAuthFromNetrc
    else:
        auth_type = HTTPBasicAuthFromNetrc

    try:
        auth = auth_type(url=options.gerrit_url)
        gerrit = GerritRestAPI(url=options.gerrit_url, auth=auth)
    except Exception as e:
        logging.error(e)
        return 1

    logging.info(message)
    try:
        stale_changes = []
        offset = 0
        step = 500
        query_terms = ["status:new", "age:%s" % options.age]
        if options.branches:
            query_terms += ["branch:%s" % b for b in options.branches]
        elif options.exclude_branches:
            query_terms += ["-branch:%s" % b for b in options.exclude_branches]
        if options.projects:
            query_terms += ["project:%s" % p for p in options.projects]