A vendor prepares paan, a betel nut-based chewable stimulant at a flower market in Kolkata, India, January 18, 2016. (Photo by Rupak De Chowdhuri/Reuters)

Haitians cross a collapsed bridge on the outskirts of Port-au-Prince, Haiti, March 24, 2016. The bridge collapsed as a truck was crossing it on March 18, according to local media. (Photo by Andres Martinez Casares/Reuters)

Salvadoran clown Cosquilla poses for a picture during the VIII Central America Clown Convention in San Salvador, El Salvador, May 18, 2016. (Photo by Jose Cabezas/Reuters)

F/A-18 fighter jet takes off from the USS Harry S. Truman aircraft carrier in the eastern Mediterranean Sea June 13, 2016. (Photo by Baz Ratner/Reuters)

A model is filmed backstage before the Jeremy Scott Fall/Winter 2015 collection presentation at New York Fashion Week February 18, 2015. (Photo by Andrew Kelly/Reuters)

Children play on a donkey cart belonging to an elderly Afghan refugee sleeping on a roadside on the outskirts of Islamabad, Pakistan, Wednesday, February 18, 2015. (Photo by Muhammed Muheisen/AP Photo)

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)

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)