An American soldier walks ahead of an MKIV (Mark IV) British-made tank, circa 1918. (Photo by Hulton Archive/Getty Images)

A Sudanese girl with half painted face watches as protesters demonstrate outside the defense ministry compound in Khartoum, Sudan, April 25, 2019. (Photo by Umit Bektas/Reuters)

A security man keeps guard during Malawi's President elect Arthur Peter Mutharika swearing in ceremony at Kamuzu Stadium in Blantyre on May 28, 2019, after a contentious election marred by allegations of fraud and vote-rigging. The Malawi Electoral Commission announced on Monday that Mutharika, who heads the ruling Democratic Progressive Party (DPP), had narrowly won last week's vote after an injunction barring the release of the results was lifted. (Photo by Amos Gumulira/AFP Photo)

Festival goers on the first day of the Glastonbury Festival at Worthy Farm in Somerset, Britain on June 26, 2019. Glastonbury Festival of Contemporary Performing Arts is a five-day festival of contemporary performing arts that takes place in Pilton, Somerset, west England, from 26 to 30 June 2019. (Photo by Yui Mok/PA Images via Getty Images)

Belgium's Crown Princess Elisabeth poses with dancers and youth after a ceremony on the occasion of her 18th birthday, outside the Royal Palace in Brussels, Belgium on October 25, 2019. (Photo by Yves Herman/Reuters)

Competitor Isaiah Webb attends the 2017 Remington Beard Boss World Beard & Moustache Championships held at the Long Center for the Performing Arts on September 3, 2017 in Austin, Texas. (Photo by Brian Cahn/ZUMA Wire/Rex Features/Shutterstock)

The driver of a Maerlitram (fairy tram), dressed as a Santa Claus, walks past a car which crashed into the tram in Zurich, Switzerland December 7, 2017. (Photo by Angelika Gruber/Reuters)

Men hang at the back of a truck loaded with farm produce along a road in Ikeja district in the commercial capital Lagos, Nigeria December 19, 2016. (Photo by Akintunde Akinleye/Reuters)