I've gone through alot of them online and must admit even with some premium sites the tutorials and more than often break or out of date. I came across this once and its the only one I would recommend, and very fast to learn. - developer.mozilla.org/en-US/docs/Learn/Server-sid…
It's pure python but partially customize by Django but either way you could build the CMS in pure python. If you follow my profile, you'll see another post recently what i've written about it, hopefully once i've got my environment setup hopefully will do some more articles :)