user
Given a cartoon image and a caption. Caption: It took us years to get somebody in the inside. Question: Generating an explanation of why this image/caption combination is funny. Answer: 
assistant
A joke about birds being undercover agents. Law enforcement agencies and governments will often undertake long-term reconnaissance operations to infiltrate organizations they want to spy on. Here, the birds have their agent, the bird on the gun, as an inside source who will report to them the activities of the bird hunter. It's funny to think that birds could plan that long, and that they have a spy agency.