School boys who attend Sri Lankan traditional dance training wait for their graduation ceremony at a Buddhist temple in Colombo, Sri Lanka January 23, 2017. (Photo by Dinuka Liyanawatte/Reuters)

A feeder trains a Siberian tiger cub at Erdaohe Tiger Park July 2, 2006 in Antu County of Yanbian Chaoxian Autonomous Prefecture, Jilin Province, China. About 15 artificially-fed Siberian tigers from Harbin Siberian Tiger Park are being trained to develop their ability to live in the wild. The wild Siberian tiger is listed as one of the most endangered species in the world, with its existing number estimated at around 400 worldwide, mainly in the northeastern part of China and the Far East of Russia. Reportedly there are more than 1,300 Siberian tigers which have been raised in China. (Photo by China Photos/Getty Images)

Young girls practice acrobatic skills in the Sichuan Provincial Art School July 14, 2008 in Chengdu of Sichuan Province, China. (Photo by China Photos/Getty Images)

Police officers with a sniffer dog check a railway as the Soyuz MS spacecraft for the next International Space Station (ISS) crew of Kate Rubins of the U.S., Anatoly Ivanishin of Russia and Takuya Onishi of Japan is ready to be transported from an assembling hangar to the launchpad ahead of its launch scheduled on July 7, at the Baikonur cosmodrome in Kazakhstan July 4, 2016. (Photo by Shamil Zhumatov/Reuters)

ESA astronaut Paolo Nespoli looks on after landing back on Earth from their Soyuz TMA-20 spacecraft on May 24, 2011 in Zhezkazgan, Kazakhstan. The mission of the Soyuz TMA-20 was launched last December to the International Space Station with the flight engineers Catherine Coleman from the United States, Russian cosmonaut Dmitry Kondratyev and Italian astronaut Paolo Nespoli. The next expedition is expected to launch this June. (Photo by Stephane Corvaja/ESA via Getty Images)

X Factor and Celebrity Big Brother starlet Chloe Khan is seen working up a sweat at her luxury home on August 30, 2016. The CBB star squeezed into a pair of super-tight leggings and a teeny crop top for a very public workout. She may be a self-made millionaire, but life wasn't always so good for Chloe Khan. The Celebrity Big Brother star, 25, has revealed she was brought up in poverty as a child in Wakefield, West Yorkshire, UK. Chloe lived with her mother on a council estate before she auditioned for the X Factor and became a playboy model. (Photo by Palace Lee)

Girls practice sit-ups during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, on May 4, 2016. China's sports system has been enormously successful since the country returned to the Olympic fold in 1980, culminating with the host nation topping the medals' table at the 2008 Beijing Olympics. And yet, with the Rio de Janeiro Games less than three months away, the system is beginning to break down due to the shifting demographics of a more prosperous nation. (Photo by Aly Song/Reuters)

Actor Rarmian Newton who plays the character Hiccup rides Toothless during a scene run through of the “How to Train Your Dragon Arena Spectacular” at Hisense Arena on March 7, 2012 in Melbourne, Australia. (Photo by Robert Cianflone/Getty Images)