I use centos 7 on a VPS. I never could get the certbot python code running so I used acme.sh. The somewhat bad news is though acme.sh is open source it was sold, but it still does work with Let's Encrypt. It might be harder to install now since it targets some other certificate company.
This was my issue with the new version of Let's Encrypt. It was solved.
getting it going with Let's Encrypt version 2
This is the code on github:
acme.sh