Show the local weather icon issue

I’m doing the “Show the local weather project” I don’t seem to be getting back URLs for the icon but instead a weird number. My weather array comes back looking like.

 "weather":[{"id":721,"main":"Haze","description":"haze"},{"id":521,"main":"Rain","description":"shower rain","icon":"09n"},{"id":300,"main":"Drizzle","description":"light intensity drizzle","icon":"09n"}]. 

As you can see weather[0] doesn’t even have an icon. but I still have no idea what to do with weather[1].icon