Gelada baboons (Theropithecus gelada) play in their enclosure at the Zoo in Zurich, Switzerland, Wednesday, May 15, 2013. (Photo by Steffen Schmidt/Keystone/AP Photo)

Eight-year-old Niu Dongfang trains at the No. 2 Beijing Shuangqiao School January 13, 2005 in Beijing, China. Most of students in the gymnastics school have to study more than five years from as young as age six before they become athletes. (Photo by Guang Niu/Getty Images)

CANNES, FRANCE - NOVEMBER 03: Italian Prime Minister Silvio Berlusconi leaves the conference centre after the first day of the G20 Summit on November 3, 2011 in Cannes, France. World's top economic leaders are attending the G20 summit in Cannes on November 3rd and 4th, and are expected to debate current issues surrounding the global financial system in the hope of fending off a global recession and finding an answer to the Eurozone crisis. (Photo by Dan Kitwood/Getty Images)

Steamed Chinese-style buns, known locally as salapao, are decorated with faces during the start of the annual 10-day vegetarian festival in Bang Saphan, southern Thailand on October 13, 2015. (Photo by Matthew Richards/Courtesy Image)

In this October 21, 2015, file photo, a young man rides a hoverboard along a Manhattan street toward the Empire State Building in New York. More than 500,000 hoverboards are being recalled after reports that they can burst into flames. The Consumer Product Safety Commission said Wednesday, July 6, 2016, it has received 99 reports of battery packs in the two-wheel motorized scooters catching fire or exploding that causing burns or property damage. The recalled hoverboards were made by eight companies. (Photo by Kathy Willens/AP Photo)

A picture made available on 17 September 2014 shows extreme athletes resting in hammocks on webbings stretched between rocks during the International Highline Meeting in Monte Piana, near Misurina, in the northern Italian Alps, Italy, 08 September 2014. (Photo by Balazs Mohai/EPA)

Gold bars from the vault of a bank and Swiss one franc coins are seen in this illustration picture taken in Zurich November 20, 2014. The “Save our Swiss gold” proposal, spearheaded by the right-wing Swiss People's Party (SVP), aims to ban the central bank from offloading its reserves and oblige it to hold at least 20 percent of its assets in gold. The referendum is scheduled for November 30. The SVP argues it would secure a stable Swiss franc. (Photo by Arnd Wiegmann/Reuters)

Russian Police academy female cadets march during a rehearsal for the Victory Day military parade at Dvortsovaya (Palace) Square in St Petersburg, Russia, Wednesday, May 7, 2014. Victory Day, marking the defeat of Nazi Germany, is Russia's most important secular holiday celebrated on May 9. (Photo by Dmitry Lovetsky/AP Photo)