So I tried to add a new CNAME record for my custom domain on Godaddy. I entered the following into their dns manager:
Points to: webapp-XXXXXXX.pythonanywhere.com
TTL: 1 hour
(I replaced the actual numbers with XXXXXXX)
When I click save, I get the following error on GoDaddy: "There was an error processing your request. Please try again. If this issue continues, contact support."
I called their support. They tried to add the record as well, but it failed. They said to check with pythonanywhere to confirm I am doing it right.