These are bobble-head pumpkin toys in two sizes.  These toys use a 3D printed base and spring and have a recess in the base that holds an 8 x 3mm magnet.

The pumpkins require support, but minimal infill (10% to 20% is fine).

This is based on two prints.  First, the pumpkin model by ArtieH (https://www.printables.com/model/242023-pumpkin).

The second parts are from the excellent bobble head collection designed by 3d-printy (https://www.thingiverse.com/thing:5409630) who supplied the original base and spring mechanism designs. See his collection of bobble-heads for more fun halloween bobblers.

Bobble-Head Assembly Tips:
The square spring hole in the pumpkin is slightly large to aid assembly, but you should also clean it up with an exacto knife to insure clean assembly. Install the spring into the pumpkin first (crazy glue is recommended). Note: The tool has one end for the short spring (S) and one end for the long spring (L). Use of the spring tool is highly recommended as it protects the spring from being damaged. Finally, install the magnet in the base (optional) and install the base on the spring using a small screwdriver to seat the spring in the base (glue is usually not needed).

Enjoy!