Snap-locking sphere container inspired by Demi-sphere

I loved the Hollow Demi-sphere http://www.thingiverse.com/thing:3068 but I was a little bit disappointed when I found out that it does not snap fit and falls apart by itself. So I remodelled it in OpenSCAD and then changed the angles of the cut out cones to get a snap-closing sphere that does not fall apart by itself. The only drawback compared to the Demi-sphere is that the two parts are not identical anymore, but they are still very good for printing as they are both flat on the bottom (the larger part is also flat on the top).