Everything Kali said is right on.
I adore my yearling Angolan and plan on picking up a male this summer. I just wish she would sit still for a decent picture.
Just wanted to add to this, they're actually from a much drier habitat, rockier habitat than ball pythons and are separated from them by a pretty substantial distance. Hopefully this URL works:
http://maps.iucnredlist.org/map.html?id=177539
Mine is actually a worse climber and less grippy than my ball pythons. What she will do, though, is sit on a tangle of maple root I have in the cage for her -- if you'd like to set up a display for an Angolan, think of flat, broad, sturdy props it can't knock over or get stuck in.