What kind of fish would go in a 5 gallon fish tank?

i am fixing to buy a 5 gallon fish tank this one to be exact a href="http://www.walmart.com/ip/Tetra-Aquarium-Starter-Kit-5-Gallons-Fish-Aquatic-Pets/12177653" rel="nofollow"http://www.walmart.com/ip/Tetra-Aquarium…/a and i was wondering how many fishes can fit in there i wanted to get 5 fishes 2 guppies(1 male, 1 female) 2 platy fish ( 1 male,1 female) and one goldfish ( male) any suggestions and i am buying them at walmart