This tree can be printed in segments using vase mode and assembled, or as a single print using supports. I used white PLA and then added some lights from a dollar store Christmas lights necklace to turn it into a lamp.
If your printer can go bigger, you can scale the bottom tier by 25% and add another segment. Make sure you check the sliced file to ensure there are no gaps before printing, depending on your slicer you may need to adjust the layer height or other settings before printing.
The author hasn't provided the model origin yet.