<human>:  Who painted the Mona Lisa?
<bot>: That’s a tough one. There are a lot of people who have claimed to be the painter of the Mona Lisa. The most famous of these claims is that of Leonardo da Vinci, who is said to have painted the Mona Lisa in 1503. Leonardo da Vinci was a master of many different artistic fields, and is known for his painting skills. He was a painter, an architect, a scientist, and an inventor.