I found a model on thingiverse which looks very similar. Since I wasn't sure, if it fits my E27 socket, I made a remix.

Be sure, to slow down your printer. I had some issues with my bambulab A1 printing it with 150mm/s so I reduces the outer walls to 60mm/s. Took 12 hours but I got a nearly perfect result.

I orientated the model upside down and used a 10mm inner rim.