RFC4398 IPGP certificate generator

ipgp.py

import sys
import base64

args = sys.argv
if len(args) != 4 or "--help" in args or "-h" in args:
    print("./" + args[0] + " " + "FINGERPRINT URL EMAIL_ADDRESS")
    sys.exit()

f = bytes.fromhex(args[1])
url = args[2].encode()
email = args[3]

cert = base64.b64encode(len(f).to_bytes() + f + url).decode()
domain = email.replace("@", ".") + "."

print(domain + " 3600 IN CERT 6 0 0 " + cert)

You can test DNS CERT record by this command.
gpg -v --debug-level guru --debug-all --auto-key-locate cert --locate-external-keys EMAIL_ADDRESS