A Polisario fighter sits on a rock at a forward base on the outskirts of Tifariti, Western Sahara, September 9, 2016. At a rocky outpost in Western Sahara, a new generation of soldiers who have never known war are mobilising as tensions resurface in one of Africa's oldest disputes after a quarter century of uneasy peace. (Photo by Zohra Bensemra/Reuters)

Host Jennifer Lopez performs during the 2015 American Music Awards in Los Angeles, California November 22, 2015. (Photo by Mario Anzuoni/Reuters)

A couple sunbath on the beach in Ostrowo, northern Poland, July 20, 2015. Picture taken July 20, 2015. (Photo by Kacper Pempel/Reuters)

Promotional staff dressed in outfits of animation characters use a mobile phone at the Global Mobile Internet Conference (GMIC) 2015 in Beijing, China, April 28, 2015. (Photo by Kim Kyung-Hoon/Reuters)

Models promote the game “Diamond Dogs” during the Gamescom 2015 fair in Cologne, Germany August 5, 2015. Hundreds of thousands of visitors will enjoy one of the world's largest computer and video game events until Sunday. (Photo by Kai Pfaffenbach/Reuters)

Models prepare backstage ahead of the Strateas.Carlucci show at Mercedes-Benz Fashion Week Australia 2015 at Carriageworks on April 13, 2015 in Sydney, Australia. (Photo by Ryan Pierse/Getty Images)

Models backstage ahead of the St George New Generation show at Mercedes-Benz Fashion Week Australia 2015 at Carriageworks on April 16, 2015 in Sydney, Australia. (Photo by Brendon Thorne/Getty Images)

A couple ride a motorcycle along a street during snow in Altay, Xinjiang Uighur Autonomous Region, China, November 8, 2015. Picture taken November 8, 2015. (Photo by Reuters/Stringer)