How to use the pygerrit2.rest.auth.HTTPBasicAuthFromNetrc function in pygerrit2

self.url = url.rstrip("/")
        self.session = requests.session()
        retry = Retry(
            total=5,
            read=5,
            connect=5,
            backoff_factor=0.3,
            status_forcelist=(500, 502, 504),
        )
        adapter = HTTPAdapter(max_retries=retry)
        self.session.mount("http://", adapter)
        self.session.mount("https://", adapter)

        if not auth:
            try:
                auth = HTTPBasicAuthFromNetrc(url)
            except ValueError as e:
                logger.debug("Error parsing netrc: %s", str(e))
                pass
        elif isinstance(auth, Anonymous):
            logger.debug("Anonymous")
            auth = None

        if auth:
            if not isinstance(auth, requests.auth.AuthBase):
                raise ValueError(
                    "Invalid auth type; must be derived from requests.auth.AuthBase"
                )

            if not self.url.endswith(GERRIT_AUTH_SUFFIX):
                self.url += GERRIT_AUTH_SUFFIX
        else:

if not options.gerrit_url:
        logging.error("Gerrit URL is required")
        return 1

    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]

def __init__(self, url):
        """See class docstring."""
        auth = _get_netrc_auth(url)
        if not auth:
            raise ValueError("netrc missing or no credentials found in netrc")
        username, password = auth
        super(HTTPBasicAuthFromNetrc, self).__init__(username, password)