Two Bulgarian tourists pose in front of the Eiffel Tower in Paris on their last day in the capital on March 24, 2014. (Photo by Franck Fife/AFP Photo)

A Dutch Military Policeman, left inside, guards part of the reconstructed cockpit, right, and forward section of the fuselage after the Dutch Safety Board presented it's final report into what caused Malaysia Airlines Flight 17 to break up high over Eastern Ukraine last year, killing all 298 people on board, during a press conference in Gilze-Rijen, central Netherlands, Tuesday, October 13, 2015. (Photo by Peter Dejong/AP Photo)

Photographers take photographs of the Large Air Tanker (LAT) C-130 Hercules, also known as “Thor”, as it drops a load of around 15,000 litres during a display by the Rural Fire Service ahead of the bushfire season at RAAF Base Richmond Sydney, Australia, September 1, 2017. (Photo by David Gray/Reuters)

Students hold their weapons before the swearing in ceremony for the military students, in Bucharest, Romania, Wednesday, October 25, 2017. The Romanian Army is proudly celebrating their Army Day and marking 100-years since the landmark battle of Marasesti, a key World War I battle in 1917 when Romanian and Russian soldiers defeated German troops, halting a German offensive. (Photo by Vadim Ghirda/AP Photo)

A woman with a snake on her body, taken in Rio de Janeiro, Brazil, April 2017. A holistic therapist uses snakes to massage her clients – claiming it cures depression and even helps victims of abuse. Instead of traditional massaging techniques, Sarah Zaad uses up to six pythons and boa constrictors on brave customers who want to relax or be treated for mental disorders. The flamboyant therapist from Rio de Janeiro, Brazil believes her snakes have a magic touch, which can benefit people by massaging their bodies. (Photo by Kadeh Ferreira/Barcroft Images)

Men dressed as Elvis Presley carry a volunteer during a street parade at the 25th annual Parkes Elvis Festival in the rural Australian town of Parkes, west of Sydney, January 14, 2017. (Photo by Jason Reed/Reuters)

A giant Iron Man statue stands next to a replica Sphinx in Chuzhou, Anhui Province, China on February 21, 2017. (Photo by Sipa Asia/Rex Features/Shutterstock)

A soldier poses with a Hythe Mk III Gun Camera during training activities at Ellington Field, Houston, Texas in April of 1918. The Mk III, built to match the size, handling, and weight of a Lewis Gun, was used to train aerial gunners, recording a photograph when the trigger was pulled, for later review, when an instructor could coach trainees on better aiming strategies. (Photo by Harry Kidd/WWI Army Signal Corps Photograph Collection via The Atlantic)