Picnic table lantern pole clamp

I wanted to design something to hold a pole right near my picnic table and found [falconphysics' V-Groove Table Clamp](https://www.thingiverse.com/thing:2399418) to be the closed to what I had in mind. Remixed it a bit to suit my need:

- Chopped off the top part.
- Change size of the opening to clamp onto the table. Now suitable for table thickness of 33mm or less.
- Cut the screws so they can easily be printed flat which inspire much more confident when screw it in tightly.