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

An officer reviews members of the honor guard as they line up before a welcoming ceremony for visiting Mozambique's President Filipe Jacinto Nyusi at the Great Hall of the People in Beijing, Wednesday, May 18, 2016. (Photo by Mark Schiefelbein/AP Photo)

A dog from the K9 Division of the Sri Lanka Army’s Commando Regiment performs during an event to mark International Children’s Day at a school in Welisara, Colombo, Sri Lanka, 01 October 2016. Sri Lanka marks the Children's Day on 01 October with more emphasis on prevention of child abuse. (Photo by M.A. Pushpa Kumara/EPA)

A couple dance tango for tourists at Caminito, a touristic hotspot of La Boca neighborhood in Buenos Aires, Argentina, October 15, 2016. (Photo by Enrique Marcarian/Reuters)

An elephant “kisses” a visitor during a show at an elephant training school in Xishuangbanna, Yunnan province, April 18, 2015. Some 16 elephants live at the school and give four 30-minute performances everyday for visitors. (Photo by Wong Campion/Reuters)

A man dressed as Hindu god Shiva, smokes during an annual Hindu religious festival locally known as Shyam Baba festival in Ajmer, in the desert Indian state of Rajasthan, April 12, 2015. (Photo by Himanshu Sharma/Reuters)

Iranian athlete Maryam Toosi practises on the rooftop of her apartment building following the closure of sports facilities as part of measures aimed at containing the COVID-19 coronavirus, in Iran's capital Tehran on May 19, 2020. The coronavirus pandemic has forced the world's athletes to keep fit in confinement. The novel coronavirus has claimed the lives of nearly 7,200 people in Iran, making it the deadliest outbreak in the Middle East. The government ordered the closure of sports facilities in mid-March as part of measures aimed at containing the virus. (Photo by Atta Kenare/AFP Photo)