An art installation formed with milk churns, made by land art artist Gerard Benoit a la Guillaume, is seen at the Chenau de Mayen in the resort of Leysin, Switzerland August 7, 2015. More than 80 milk churns were placed between the Tour d'Ai and the Tour de Mayen summits at an altitude of 2,000 meters (6,561 feet) above sea level under the direction of the artist, to be photographed for his ongoing art project entitled “Milk churns without borders”. (Photo by Denis Balibouse/Reuters)

Two 70 thousand RMB (about 11,310 USD) robots carry dishes and offer service for customers at a robot themed restaurant at Chunxi Road in Chengdu, China, December 11, 2014. The restaurant has 10 robots to serve as waiters. Each robot can carry simple dishes and offer simple greetings. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

A woman looks at a swimmer getting herself warm after the annual Christmas winter swimming competition in the Vltava river in Prague December 26, 2014. (Photo by David W. Cerny/Reuters)

A dancer poses with a new installation of art by British graffiti artist Banksy painted on the front door of the Hustler Club in New York, October 24, 2013. Known for his anti-authoritarian black-and-white stenciled images, which have sold at auction for upwards of $2 million, the British street artist is treating New Yorkers to a daily dose of spray-painted art – while eluding the police and incurring the wrath of New York Mayor Michael Bloomberg. (Photo by Eric Thayer/Reuters)

People walk during a polluted day in Shenyang, Liaoning province, March 31, 2016. (Photo by Reuters/Stringer)

Winners of a competition enjoy a meal 450ft up on the roof of a central London skyscraper on August 21, 2018, as Deliveroo recreates “Lunch Atop a Skyscraper”, the photograph taken during the construction of the Rockefeller Center in New York City, 1932. (Photo by Jonathan Brady/PA Images via Getty Images)

Toni Braxton performs at the Hard Rock Events Center held at the Seminole Hard Rock Hotel & Casino in Hollywood, FL on January 29, 2019. (Photo by INSTARimages.com)

An Iraqi military vehicle passes displaced Iraqi boys returning to their homes in West Mosul's Oreibi neighbourhood after government forces retook control of the area from the Islamic State (IS) group during the ongoing offensive against the jihadists on May 21, 2017. (Photo by Ahmad Al-Rubaye/AFP Photo)