Festival goers arrive for the Glastonbury festival at Worthy Farm, in Somerset, England, Thursday, June 23, 2016. (Photo by Guy Bell/Rex Features/Shutterstock)

A fighter of Libyan forces allied with the U.N.-backed government runs for cover during a battle with Islamic State fighters in Sirte, Libya, July 31, 2016. (Photo by Goran Tomasevic/Reuters)

A man holds his umbrella during snowfall on the Areopagitou pedestrian street beneath the Acropolis hill during snowfall in Athens, Greece, January 10, 2017. (Photo by Alkis Konstantinidis/Reuters)

A migrant boy sits on railway tracks at a train station in Tovarnik, Croatia, September 20, 2015. (Photo by Antonio Bronic/Reuters)

Archie, a Chinese Crested dog, sits with his tongue out before the start of the 20th Annual Ugliest Dog Competition at the Sonoma-Marin Fair June 20, 2008 in Petaluma, California. Owners of ugly dogs travel to Petaluma from all over the country to participate in the annual contest. (Photo by Justin Sullivan/Getty Images)

A young arab boy, armed with a rifle and a knife, in the Aden Protectorate near Yemen. (Photo by Richards/Fox Photos/Getty Images). February 1938

Soldiers of the 70th division of the American 7th Army hold up a Nazi flag and a portrait of Adolf Hitler, taken during the World War II capture of Saarbrucken. (Photo by Horace Abrahams/Keystone/Getty Images). 22nd March 1945

A young exhibitor arrives with her kitten on a lead at the National Cat Club show at Crystal Palace, London. (Photo by Fox Photos/Getty Images). 2nd December 1931