What do I put in my 4 gal

Somehow I ended up with a 4 gallon fish tank. Didn’t even know they made them that size, thought it was like 1,5,10 gal. What in the world can I put in here besides shrimp? Preferably something with a short lifespan, this is my tank at college and I’d prefer not to bring it back and fourth over the summer and stress the poor creatures out, but idk if that’s a possibility.