def METHOD_NAME(client, authzs):
    cleanup_hosts = []
    for a in authzs:
        c = get_chall(a, challenges.DNS01)
        name, value = (c.validation_domain_name(a.body.identifier.value),
            c.validation(client.net.key))
        cleanup_hosts.append(name)
        challSrv.add_dns01_response(name, value)
        client.answer_challenge(c, c.response(client.net.key))
    def cleanup():
        for host in cleanup_hosts:
            challSrv.remove_dns01_response(host)
    return cleanup