Small Harry Potter Death Hollow Light

Print in place 

1. Cut a piece of paper to length
2. Add tape on the paper to make it less easy to bed/mess up
3. Slide bottom of the paper in first, then slide in the front of it
4. Add LEDs well wrapped up with the battery holder in its housing
5. (optional) Secure with hot glue
6. Done

LEDs used: https://amzn.eu/d/hui3dXP

While not directly built upon it, this model is greatly inspired from @SvenTrautmann_471307's design, but small, in one piece, and without the HP logo.