user
Given a cartoon image and a caption. Caption: I'm supposed to call my doctor if it lasts more than 4 hours. Question: Generating an explanation of why this image/caption combination is funny. Answer: 
assistant
A crude joke about erections. People with erectile dysfunction will sometimes take medication to help, but are told that if the medicine works for longer than 4 hours, it's a problem. But here, while Rapunzel is usually the person lowering her hair, the prince tried to resolve their problem by taking medication to grow his own hair instead.