A cosplayer uses moving stairs during the first public day of the world's largest computer games fair Gamescom in Cologne, Germany August 23, 2017. (Photo by Wolfgang Rattay/Reuters)

A participant dances as approximately 70,000 people from all over the world gathered for the annual Burning Man arts and music festival in the Black Rock Desert of Nevada, U.S. on August 29, 2017. (Photo by Jim Urquhart/Reuters)

Models wait backstage ahead of the Eugenia Kim Spring/Summer 2018 fashion show during New York Fashion Week in New York, U.S., September 10, 2017. (Photo by Amr Alfiky/Reuters)

A model gets final adjustments back stage before participating in a plus size fashion show in Nairobi, Kenya, October 7, 2017. (Photo by Baz Ratner/Reuters)

Eagle Prime (MK3), a giant robot by MegaBots Inc. which manufactures giant piloted humanoid fighting robots headquartered in Berkeley, California on October 18, 2017. (Photo by Courtesy Michael Mauldin/Reuters/MegaBots Inc)

U.S. President Donald Trump boards Air Force One to depart for Vietnam from Beijing Airport in Beijing, China on November 10, 2017. (Photo by Jonathan Ernst/Reuters)

A mahout guards the elephants during the annual Vrischikolsavam festival, which features a colourful procession of decorated elephants along with drum concerts, at a temple in Kochi, India, November 18, 2017. (Photo by Sivaram V/Reuters)

People look at the paintings depicting Russian president Vladimir Putin dressed as Father Frost, Russian equivalent of Santa Claus, at the “SUPERPUTIN” exhibition at UMAM museum in Moscow, Russia on December 6, 2017. (Photo by Maxim Shemetov/Reuters)