A hippopotamus is sprayed with water on a hot summer day at Anna National Zoological Park in Chennai, India on April 26, 2017. (Photo by Arun Sankar/AFP Photo)

Police officers clear the area near Borough market at London Bridge on June 3, 2017 in London, England. Police have responded to reports of a van hitting pedestrians on London Bridge in central London. (Photo by Dan Kitwood/Getty Images)

Attendee Emily poses for a picture at 2017 Comic-Con International on July 20, 2017 in San Diego, California. (Photo by Mike Blake/Reuters)

Iraqi security forces ride in vehicles travelling to Mosul to fight against militants of Islamic State at an Iraqi army base in Camp Taji in Baghdad, February 21, 2016. (Photo by Ahmed Saad/Reuters)

A Soyuz capsule carrying International Space Station (ISS) crew members U.S. astronaut Scott Kelly, Russian cosmonauts Sergei Volkov and Mikhail Korniyenko descends beneath a parachute near the town of Dzhezkazgan (Zhezkazgan), Kazakhstan, March 2, 2016. (Photo by Kirill Kudryavtsev/Reuters)

A man flies a kite made of 110 Tukkal or paper lanterns for the Hindu festival of “Makar Sankranti”, which marks the start of spring, in Ahmedabad January 13, 2011. (Photo by Amit Dave/Reuters)

People sit on a cart with a camel tied to it during “Temeenii bayar”, the Camel Festival, in Dalanzadgad, Umnugobi aimag, Mongolia, March 6, 2016. On the steppes of the Gobi Desert, the crowd urges on Bactrian camels laden down with all that's needed to build and live in a traditional Mongolian tent. Guinness World Records classes the 15 km race thatÕs part of the two-day festival as the largest camel race in the world, drawing 1,108 participants. The winning camel romped home in 35 minutes and 12 seconds, according to the records website. (Photo by B. Rentsendorj/Reuters)

People hold up face masks with William Shakespeare's portrait during celebrations to mark the 400th anniversary of the playwright's death in the city of his birth, Stratford-Upon-Avon, Britain, April 23, 2016. (Photo by Dylan Martinez/Reuters)