Can the word "comedy" be used as adjective?

At 1:32 in this YouTube video (https://youtu.be/8l6T3fwxAyw), the character said, “Wanna see an impression of my dad?” and the other answered, “Sure” then “Haha! Comedy.”

Does the second guy use “comedy” as adjective to mean it’s funny or he literally suggest the first guy’s impression is like “a comedy”?