This filmmaker is trying to preserve an ancient Chinese language invented as a secret code between women

Hundreds of years ago, it was common for Chinese women's feet to be bound, making it almost impossible for them to walk freely by themselves. They also weren't allowed an education, and they spent their days locked in their rooms, embroidering and making crafts. So, women came up with a new language that men couldn't understand - Nushu - and wrote it onto handmade fans to communicate with each other. Now a filmmaker is trying to raise awareness to preserve it before it is lost.