A Iraqi soldier of the 9th division is seen within a Humvee in Shyma district in Mosul, Iraq, Tuesday, December 6, 2016. Iraqi forces, backed by the U.S.-led international coalition, launched a campaign in October to retake Mosul, the country's second largest city and IS's last major urban bastion in Iraq. (Photo by Manu Brabo/AP Photo)

An Iraqi special forces soldier shot dead an Islamic State suicide bomber in Mosul, Iraq March 3, 2017. (Photo by Goran Tomasevic/Reuters)

A tattoo is displayed on the arm of a girl during Bandung Body Art Festival at in Bandung, West Java, on December 7, 2014. Upon its establishment in 2010, founders of the Bandung Body Art Festival sought to celebrate an art form that was once taboo and associated with criminals. Tattoos are now an increasingly acceptable part of Indonesia’s urban landscape, and the annual event this year continued its campaign with 45 tattoo artists offering their services for free at the Ganesha Cultural Center. (Photo by Rezza Estily/JG Photo)

A woman reacts as she joins around a thousand New Year swimmers, many in costume, braved freezing conditions in the River Forth in front of the Forth Rail Bridge during the annual Loony Dook Swim on January 1, 2013 in South Queensferry, Scotland. Thousands of people gathered last night to see in the New Year at Hogmanay celebrations in towns and cities across Scotland. (Photo by Jeff J. Mitchell)

Keith Haubrich of Seattle, Wash., reacts to the crowd while competing in the Dali Moustache division during the fourth annual Just For Men National Beard and Moustache Championships Saturday, September 7, 2013 in New Orleans. Haubrich went on to win the gold medal for the Dali division.Contestants competed in 18 different categories including Dali, full beard natural and sideburns.(Photo by Susan Poag/AP Photo)

Model Heidi Klum and TV personality Nick Cannon speak onstage during Nickelodeon's 24th Annual Kids' Choice Awards at Galen Center on April 2, 2011 in Los Angeles, California. (Photo by Kevork Djansezian/Getty Images)

Two guards perform an execution in China, one holding the gun, the other holding a mask over the victim's face. (Photo by General Photographic Agency/Getty Images). Circa 1925

Stones collected and categorised by shape (fish) are seen at the home workshop of Luigi Lineri in Zevio, near Verona, Italy, June 10, 2016. Luigi Lineri's home workshop is covered in stones – tens of thousands of them. They resemble animal heads, human faces and other forms, and the artist and poet believes may have been shaped by prehistoric humans. (Photo by Alessandro Bianchi/Reuters)