Print with support!
There are two versions. The first is flat bottomed and works like a real jack o'lantern -- just drop in a LED tea light through the top.
The design with the hole through is more ambitious. The LED light is meant to friction fit in the hole, but it doesn't really work very well.
Perhaps in an update I'll be able to reliably hold inserted tea lights in place, but as it stands the tea light will either fall out unless wrapped in tape or else the hole will print too small and you'll need to trim it down.