Potato Harvest - What is it?

by Carla
(Tacoma WA)

I grow potatoes every year, but this year I found a surprise. On the end of a couple of potato plants are these little round fruits or vegies.

I have gathered them up. They look something like a tomato, a green tomato. They grow in groups of 3 to 5.

Are those little things eatable?

Thank you Carla.