A Kevo smart lock is demonstrated during the 2015 International Consumer Electronics Show (CES) in Las Vegas, Nevada January 4, 2015. The lock, which opens with a smart phone App and a touch, is smart enough to know what side of the door you are on and won't accidentally unlock the door when you are inside. A new subscription service offers unlimited e-keys and other benefits, a representative said. (Photo by Steve Marcus/Reuters)

A girl plays with coloured chicks for sale prior to Easter celebrations in Byblos, Lebanon on March 22, 2015. (Photo by Jamal Saidi/Reuters)

Graffiti is painted on the bathroom walls at a restaurant in the Williamsburg area of Brooklyn borough in New York, United States, October 1, 2015. Some 2.4 billion people around the world don't have access to decent sanitation and more than a billion are forced to defecate in the open, risking disease and other dangers, according to the United Nations. To mark World Toilet Day on November 19, Reuters photographers captured pictures of toilets in cities, towns and villages around the globe. (Photo by Shannon Stapleton/Reuters)

A representative of Makinarium production, specialized in special visual effects, displays a latex mask for horror movie on a stand inside the Festival Palace during the 69th Cannes Film Festival in Cannes, France, May 14, 2016. (Photo by Regis Duvignau/Reuters)

A staff member sets up a ROBOTLEO robot at the Global Mobile Internet Conference (GMIC) 2017 in Beijing, China April 28, 2017. (Photo by Jason Lee/Reuters)

French firemen wearing chemical protective suits take part in a mock chemical attack exercise at the Geoffroy Guichard stadium in Saint-Etienne, France, April 4, 2016 in preparation of security measures for the UEFA 2016 European Championship. (Photo by Robert Pratta/Reuters)

Chinese models with animal-themed body paintings pose during a campaign for animal protection at Sanya Color Zoo in Sanya city, south China's Hainan province, 10 January 2016. The girls wearing strapless bras and short pants only were colored with animal-themed paintings such as zebra, cheetah, tiger and peacock. They paraded throughout the newly-opened Sanya Color Zoo and met visitors to take pictures, causing envies from netizens living in north China who are suffering chills. (Photo by Imaginechina/Splash News)

A performer dressed as Empress Huang of the China's Forbidden City takes part in a musical performance at a shopping mall in Kuala Lumpur on January 22, 2017 as part of the upcoming Lunar New Year celebrations marking the Year of the Rooster. (Photo by Manan Vatsyayana/AFP Photo)