Police officers display their AI-powered smart glasses in Luoyang, Henan province, China on April 4, 2018. (Photo by Reuters/China Stringer Network)

Yoga students take a class with Nigerian Dwarf goats held by the 'Hello Critter Goat Yoga' team at the Golden Road Pub in Los Angeles, California on May 7, 2018. The goat yoga fitness craze is sweeping the United States with classes now held in pubs, farms and halls across the country. (Photo by Mark Ralston/AFP Photo)

North Korean youngsters sing and play accordions to entertain foreign visitors including United Nations Secretary General Kurt Waldheim, who visited Pyongyang, May 4, 1979. Visitors report music education in North Korea begins at an early age and is taken seriously by children and adults. (Photo by Peter Arnett/AP Photo)

British band Florence and the Machine performs at the Bilbao BBK Live festival in Bilbao, Spain, early 13 July 2018. Bilbao BBK Live festival runs from 12 July to 14 July 2018. (Photo by Miguel Tona/EPA/EFE)

Tightrope walker Tatian-Mosio Bongonga hangs from a tightrope as she pauses while scaling the Monmartre hill towards the Sacre Coeur Basilica (not pictured) in Paris, France, July 20, 2018. (Photo by Philippe Wojazer/Reuters)

Chase Outlaw dodges Cochise after being bucked off in the final round of the PBR Unleash the Beast bull riding event at Madison Square Garden on January 06, 2019 in New York City. (Photo by Sarah Stier/Getty Images)

In this January 16, 2019 photo, a sculpture of a Plesiosaur is displayed at an exhibit about the studies of researchers from the National Museum made in Antartica, during a media presentation of the exhibit in Rio de Janeiro, Brazil. The National Museum will inaugurate on Jan. 17 their first exhibition after the fire, held at the building that houses the Cultural Center and Museum of Brazil's Mint. (Photo by Leo Correa/AP Photo)

A man walks his dog as the sun sets in a park in Frankfurt, Germany, Monday, September 18, 2017. Cool damp weather is set to continue in this part of Germany for the next few days with temperatures in the mid teens Celsius. (Photo by Michael Probst/AP Photo)