People walk during a polluted day in Shenyang, Liaoning province, March 31, 2016. (Photo by Reuters/Stringer)

A man rides his loaded tricycle next to three schoolgirls in Shanghai on December 11, 2015. (Photo by Johannes Eisele/AFP Photo)

A woman plays with a kitten inside of a line house in downtown Shanghai April 12, 2015. (Photo by Carlos Barria/Reuters)

Police officers display their AI-powered smart glasses in Luoyang, Henan province, China on April 4, 2018. (Photo by Reuters/China Stringer Network)

Video bloggers stream live broadcast of an event to celebrate the fourth birthday of the world's only giant panda triplets, Meng Meng, Shuai Shuai and Ku Ku, at Chimelong Safari Park in Guangzhou, China July 29, 2018. (Photo by Bobby Yip/Reuters)

A father crosses a road with his twin daughters in Shanghai, China September 28, 2018. (Photo by Aly Song/Reuters)

An army dog stands up as retiring soldiers salute their guard post before retirement in Suqian, Jiangsu province, China on November 29, 2017. (Photo by Reuters/China Stringer Network)

In this picture taken on December 13, 2017, a woman commutes on a street on a cold day in Baoding. As temperatures dipped below freezing in a northern Chinese village, a group of parka-clad women tried to stay warm as they played mahjong around a small gas stove in a grocery store. (Photo by Fred Dufour/AFP Photo)