Varo DNS Authenticator plugin for Certbot.
pip install certbot-dns-varo
Your credentials ini file should look like this:
dns_varo_api_key = r4n8pvj82q8bdn120y7uzp5yayebgpju
certbot certonly --authenticator dns-varo --dns-varo-credentials /path/to/your/varo.ini -d yourdomain.tld