pw.py

for current_attempt in range(MAX_DNS_ATTEMPTS):
    print("Checking for DNS record, attempt: {}/{}".format(current_attempt+1, MAX_DNS_ATTEMPTS))

    try:
        dns_answer = dns.resolver.query(host, 'TXT')

        if not dns_answer:
            continue

        for dns_rrset in dns_answer.rrset:
            dns_text = dns_rrset.to_text()

            # DNS library quotes returned strings - for comparisons we
            # need to remove them
            if dns_text.startswith('"') and dns_text.endswith('"'):
                dns_text = dns_text[1:-1]

            print("DNS response: " + dns_text)
            print("Challenge: " + challenge)

            if dns_text == challenge:
                break

    except dns.exception.Timeout:
        print("DNS timeout, quitting...")
        sys.exit(1)
    except dns.resolver.NXDOMAIN:
        pass
    except dns.resolver.NoAnswer:
        pass

    time.sleep(LOOKUP_SLEEP_SECONDS)
    current_attempt += 1
else:
    print("Failed to find record for: " + domain)
    sys.exit(1)