Members of security forces secure Tahrir Square in Cairo, Egypt, November 11, 2016. Egypt imposed a big security clampdown in its cities on Friday as mass demonstrations called to protest against austerity measures failed to take place. Riot police and armored vehicles filled the otherwise empty streets of central Cairo, but most people stayed at home. (Photo by Mohamed Abd El Ghany/Reuters)

A boy poses for a photo as he plays with a homemade toy gun in Qayara, south of Mosul, Iraq, Tuesday, November 22, 2016. For months, residents of the Iraqi town of Qayara have lived in the darkness from a cloud of toxic fumes released by oil fields lit by retreating Islamic State fighters. (Photo by Felipe Dana/AP Photo)

Two Tibetan women wearing traditional striped aprons, elaborate headdresses and abundant jewellery. Original Publication: From a photograph by Shephard. (Photo by Hulton Archive/Getty Images). Circa 1910

A woman toes a tube carrying a man during the Ice and snow carnival at Taoranting park in Beijing, China, January 25, 2016. (Photo by Kim Kyung-Hoon/Reuters)

The head of a mountain ram is attached to a wooden column at the site used for shamans' rituals in the Aldyn Bulak area on the bank of the Yenisei River during sunset outside the village of Elegest, Tuva region, Southern Siberia, Russia, October 7, 2015. The region is inhabited by Tuvans, historically cattle-herding nomads, who nowadays practise two main confessions – Buddhism and Shamanism. (Photo by Ilya Naymushin/Reuters)

These are the stomach-churning pictures of the swing at the end of the world – a rickety wooden swing hanging over a precipice 2,660 metres above sea level – and not a seatbelt in sight. (Photo by Caters News)

Playboy Bunny, Penny (surname not given), is helped into her costume as she prepares herself before starting work at the Playboy Club on July 26, 2016 in London, England. The Playboy Club London is celebrating its 50th anniversary this year and will mark the event with a “Touch of Gold” party on July 29. (Photo by Carl Court/Getty Images)

A woman photographs a Norwegian spruce Christmas tree from Oslo after it was lit at Trafalgar Square in central London, December 4, 2014. (Photo by Toby Melville/Reuters)