What is a ping?

Ping, Pang and Pong are ministers of the Emperor in Puccini’s opera “Turandot”

Early twentieth century cultural sensitivity at its best! Also the characters “Osaka” and “Kyoto” in Mascagni’s “Iris” set in Japan, or the heroine “Ah-Joe” in Leoni’s “L’oracolo” set in SFs Chinatown 1905. Picturesque then but embarrassing now.