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

People look at huge waves crashing on the San Esteban de Pravia seafront, northern Spanish region of Asturias February 8, 2016. (Photo by Eloy Alonso/Reuters)

A paramilitary police officer (right) turns around as hostesses line up for roll call ahead of the Beijing International Automotive Exhibition in Beijing, China, on Monday, April 25, 2016. Tesla Motors Inc. and BYD Co. are among manufacturers showing 147 new-energy vehicles at this year's show. (Photo by Qilai Shen/Bloomberg)

A staff member feeds a rabbit at the Bunny Style Hotel in Hong Kong, Wednesday, January 18, 2023. With the lifting of COVID restrictions, Hong Kongers are traveling again and some of those who keep rabbits at pets are booking them into a rabbit resort where they are fed, exercised and pampered with spa treatments. The Lunar New Year of the Rabbit is shining a particular spotlight on the popularity of the animals in the crowded city of tiny apartments. (Photo by Anthony Kwan/AP Photo)

Egyptian bootblacks cleaning a European's shoes in Cairo. (Photo by Hulton Archive/Getty Images). Circa 1870

Two sailors from HMS Fury enjoy a smoke with two women in bathing suits on a beach in Jersey, where their ship is on a visit. (Photo by William Vanderson/Fox Photos/Getty Images). 29th June 1935

A polar bear fast asleep at London Zoo. (Photo by Fox Photos/Getty Images). 1961

A model walks down the runway at the 13th China International Young Fashion Designers Contest during China Fashion Week on March 25, 2005 in Beijing, China. (Photo by China Photos/Getty Images)