This was made with blender in sculpting mode..
Print each of the halves as oriented in the print files. I printed the stalk in white and the top in red. From memory, this needed supports.
There is a hole in the stem which you can thread a mains lead through and fill the stalk with a coil of fairy lights. Then just place the top of the mushroom over the lights. No need to secure it. This lets the light leak out the sides too.
The author marked this model as their own original creation.