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)

An Israeli boy swims next to sheep belonging to a Palestinian farmer in the West Bank village of Al-Auja in the Jordan Valley on April 8, 2015 during the Jewish Passover holiday. Thousands of Israelis spent the day outdoors, picnicking and touring the country during the eight-day Passover holiday, which commemorates the Israelites' exodus from Egypt some 3,500 years ago. (Photo by Menahem Kahana/AFP Photo)

Robot couple Xiaolan (L) and Xiaotao carry trays of food at a restaurant in Jinhua, Zhejiang province, China, May 18, 2015. The restaurant, which opened on Monday, has two robots delivering food for customers. The robots were designed as a couple, Xiaolan and Xiaotao, according to local media. (Photo by Reuters/Stringer)

A child walks to an installation made from fallen leaves by college students, in shape of a sofa, to call for people's attention to environment protection, in Hangzhou, Zhejiang province, China, December 6, 2016. (Photo by Reuters/China Daily)

A folk performer (front R) with make-up and props takes part in a “Blood Shehuo” parade, during a performance in Linyi county, Shanxi province March 21, 2015. “Shehuo” is the common name of Chinese traditional activities consisting of folk performances in northern China. The “Blood Shehuo” performers use make-up and props to re-enact scenes of horror in classic Chinese novels like Water Margin. (Photo by Reuters/Stringer)

“Red Land: Sunset Cloud Village is one of the most picturesque places in Red Land, China. As its name indicates, it's best to see before sunset. The reddish brown soil turns redder after rainfall and after farmers plow the land”. (Photo and comment by Peng Jiang/National Geographic Photo Contest via The Atlantic)

A little girl takes a picture of a lion in the zoo in Frankfurt, Germany, Tuesday, September 13, 2016. (Photo by Michael Probst/AP Photo)

People take photos as an Ariane 5 space rocket with a payload of four Galileo satellites lifts off from ESA's European Spaceport in Kourou, French Guiana, on November 17, 2016. Ariane 5 successfully launched on November 17 four satellites which will be part of the Galileo global satellite navigation system. (Photo by Jody Amiet/AFP Photo)