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)

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)

People stand in the middle of the graves and in front of giant kites in the cemetery of Santiago Sacatepequez, Guatemala, November 1, 2015. Dating back 116 years, the tradition of flying kites in the cemetery of of Santiago Sacatepequez, integrates the Catholic feast of All Saints with ancient Mayan practices of honouring the dead. It is believed that the kites connect the living and the dead during the all saints day celebration. (Photo by Jorge Dan Lopez/Reuters)

Men hang at the back of a truck loaded with farm produce along a road in Ikeja district in the commercial capital Lagos, Nigeria December 19, 2016. (Photo by Akintunde Akinleye/Reuters)

A woman travels on a train stopping at a subway station visited by foreign reporters in central Pyongyang, North Korea on April 14, 2017. (Photo by Damir Sagolj/Reuters)

Iraqi soldiers from 9th Armoured Division give drops of water to a dehydrated child rescued earlier by soldiers at the frontline, during the ongoing fighting between Iraqi forces and Islamic State militants near the Old City in western Mosul, Iraq June 13, 2017. (Photo by Erik De Castro/Reuters)

A sledding dog is covered in ice after spending the night in the open air with his musher at the polar base of Val-Cenis, as they ready for the next stage of the 12th edition of “La Grande Odyssee” sledding race across the Alps on January 17, 2016 in Val Cenis Lanslevillard. (Photo by Jean-Philippe Ksiazek/AFP Photo)

Pokot men carry a part of a carcass of a bull killed by a young man during an initiation ceremony in Baringo County, Kenya, January 20, 2016. Far from the bustling city of Nairobi, in an isolated corner of Kenya's Rift Valley, young men from the Pokot community spear a bull in a ceremony called Sapana that takes them into adulthood. (Photo by Siegfried Modola/Reuters)