"I know what porn looks like. I know what children look like."

Do you though?

Some children look like adults (17 vs 18, etc). Some adults, look younger than they actually are. How do we tell the difference between porn and art, such as nude scenes in movies, or even ancient sculptures? It doesn't seem like an agent would be able to make these determinations without a significant amount of training, and likely added context about any images it processes.