A simple fat-ball bird feeder modified for easier printing by eliminating a floating overhang. No need for supports, no need to tune the printer for minimum sag. The infill could have been thinner or a different shape, but that's what I came up with.

It's literally this ad hoc openSCAD snippet with half the resulting triangles thrown out in the slicer.

Also the cap has now an indentation to make it easy to center the loop piece for gluing in place. Print it flat, but with selective infill.

Printed mine in PETG at 0.2 mm and 0.4 mm nozzle as that's my personal preference.