Lighting Christmas Tree RGB LED - auto change color - button cell - DIY

This is a DIY project, which you can create pretty easily. The result is a Christmas tree which changes it's color automatically, looking really cool and making a good mood in your home.
https://www.youtube.com/watch?v=qkzKGrSLb4A

You will need:
- the attached 3D models printed out (the placeholder can be printed out simply with normal settings, but the Christmas tree should be printed out in vase mode - https://goo.gl/YAvigH)
- a 5mm Cycling RGB LED (https://goo.gl/gdDYvB)
- one cr3032 c