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

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)

This photo taken on August 7, 2016 shows mahjong enthusiasts playing mahjong under water in a swimming pool at a diving club in the Chinese city of Chongqing. Only participants with proper diving certification were allowed to take part in the underwater competition. (Photo by AFP Photo/Stringer)

A toddler sits on the winner of the giant pumpkin category during the RHS (Royal Horticultural Society) London Harvest Festival Show at RHS Lindley Halls on October 6, 2015 in London, England. The traditional harvest themed show runs October 6-7 and showcases a wide range of late summer grown fruit and vegetables. (Photo by Ben Pruchnie/Getty Images)

A girl poses in her costume during a Halloween party at a mall in Quezon city, Metro Manila October 24, 2015. (Photo by Ezra Acayan/Reuters)

Vietnamese military personnel in traditional dress take part in a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

Crowds gather and watch the launch of NASA space shuttle Endeavour from Kennedy Space Center on the beach May 16, 2011 in Cocoa Beach, Florida. (Photo by Roberto Gonzalez/Getty Images)

Thai residents party after sunset in the water on a flooded street along the swollen Yom river August 24, 2011 Phinchit, Thailand. The death toll has climbed to over 37 as 13 provinces remain flooded with 1.5 million affected. In Phinchit 110,000 people's homes have been flooded by nearby overflowing rivers. (Photo by Paula Bronstein /Getty Images)