It follows her take of Guns N'Roses Sweet Child O'Mine, released last year, which has been viewed more than 1.2 million times. Canada-based Kwan says:

"I've seen Metallica in concert twice. My childhood dream is to perform on the big stage like them. If they ever did a collaboration with a guzheng, this is how I imagine it."

The guzheng, an early form of zither, was invented around 2500 years ago and became the most popular instrument in China over the next millennium. The modern version usually has 21 strings.