A woman instructs a boy on how to pose for pictures in front of a mural depicting Soviet pilot Valery Chkalov – who took a non-stop flight over the Arctic and landed in the US state of Washington in 1937 – at Chkalovskaya metro station in Moscow on August 14, 2019. (Photo by Yuri Kadobnov/AFP Photo)

Militia members march in formation past Tiananmen Square during the military parade marking the 70th founding anniversary of People's Republic of China, on its National Day in Beijing, China on October 1, 2019. (Photo by Thomas Peter/Reuters)

A female police officer stands in the street during an anti-government protest in Santiago, Chile, Saturday, October 26, 2019. Chile has been facing days of unrest, triggered by a relatively minor increase in subway fares. The protests have shaken a nation noted for economic stability over the past decades, which has seen steadily declining poverty despite persistent high rates of inequality. (Photo by Rodrigo Abd/AP Photo)

A demonstrator holds up her fist, in front of police officers during a protest, organised by Black Lives Matter Belgium, against racial inequality in the aftermath of the death in Minneapolis police custody of George Floyd, in central Brussels, Belgium on June 7, 2020. (Photo by Yves Herman/Reuters)

Old Heidelberg, Dog with Pipe, 1905. (Photo by Detroit Publishing Company)

Russian soldiers write home while serving on the Eastern Front during World War I, circa 1915. (Photo by Hulton Archive/Getty Images)

A gibbon drinks from a soft drink bottle, given by a tourist, at a zoo in Kunming, Yunnan province, June 18, 2015. (Photo by Wong Campion/Reuters)

Labourers break fast outside a shop in a market on the first day of the Muslim holy month of Ramadan in Karachi, Pakistan June 7, 2016. (Photo by Akhtar Soomro/Reuters)