Members of the Indian Border Security Force (BSF) demonstrate their skills on motor-bikes during the BSF Golden Jubilee Day celebration in New Delhi on December 1, 2015. (Photo by Money Sharma/AFP Photo)

A woman stands in front of graffiti depicting Venezuela's late former President Hugo Chavez, right, and revolutionary hero Simon Bolivar, in downtown Caracas, Venezuela, Wednesday, October 25, 2017. (Photo by Rodrigo Abd/AP 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)

Aerobatic pilot Sean D. Tucker flies in the two-seat Oracle Extra airplane over downtown Chicago skyline, Wednesday, June 8, 2016. Tucker will perform before the start of of the America's Cup World Series racing on Saturday and Sunday. (Photo by Kiichiro Sato/AP Photo)

A man stands near bodies of his young relatives after an airstrike in the rebel held Douma neighbourhood of Damascus, Syria August 22, 2016. (Photo by Bassam Khabieh/Reuters)

High-wire artist Kane Petersen successfully walks a tightrope 300 metres above the ground at Eureka Skydeck on September 16, 2015 in Melbourne, Australia. The walk was the highest tightrope walk ever attempted in the Southern Hemisphere. The stunt is to mark the arrival of the film “The Walk” to Australian cinemas in October. The stunt saw Kane mimic the film's French high-wire artist Philippe Petit, who successfully walked between the twin towers of the World Trade Center in 1974. (Photo by Scott Barbour/Getty Images)

Models present Victoria Secret Fantasy Bras priced at $2 million each during a media preview of the Singapore JewelFest in Singapore October 8, 2015. The festival which is in its 13th year, sees over 42 Asian designers participating and over $300 million worth of jewels for sale. It opens from October 9 to 18. (Photo by Edgar Su/Reuters)

People slide down a 1,082 feet (330 metre) long inflatable water slide in Hong Kong, China August 22, 2015. (Photo by Tyrone Siu/Reuters)