People ride on a truck as they return to their families ahead of the Eid al-Adha festival in Khartoum September 11, 2016. (Photo by Mohamed Nureldin Abdallah/Reuters)

Visitors watch as Grigory Broverman, a member of the Cryophile winter swimmers club, pours a bucket of cold water over his 6-year-old daughter Liza during a flash mob, part of a celebration of Polar Bear Day at the Royev Ruchey Zoo in a suburb of the Siberian city of Krasnoyarsk, Russia, November 29, 2015. The air temperature was around minus 5 degrees Celsius. (Photo by Ilya Naymushin/Reuters)

A family dressed in traditional chinese clothes celebrates the Chinese New Year in Chinatown in Bangkok, Thailand February 8, 2016. (Photo by Jorge Silva/Reuters)

An Indian street vendor selling bananas naps on his fruit cart at the roadside in New Delhi on June 3, 2015. (Photo by Money Sharma/AFP Photo)

Potters colour earthen lamps at a workshop ahead of the Hindu festival of Diwali in Amritsar October 15, 2014. Earthen lamps are sold in large numbers during Diwali, the annual Hindu festival of lights, as people use them to decorate their homes. (Photo by Munish Sharma/Reuters)

A person dressed like a zombie walks during the 2015 Comic-Con International Convention in San Diego, California July 9, 2015. The pop-culture held at the San Diego Convention Center event runs July 9-12. (Photo by Mario Anzuoni/Reuters)

Pakistani children cool themselves off in a stream in Peshawar, Pakistan, Monday, June 29, 2015, during Muslim's fasting month of Ramadan. (Photo by Mohammad Sajjad/AP Photo)

Festival-goers enjoy the mud during the annual Boryeong Mud Festival at Daecheon Beach on July 18, 2015 in Boryeong, South Korea. The mud, which is believed to have benefical effects on the skin due to its mineral content, is sourced from mud flats near Boryeong and transported to the beach by truck. (Photo by Chung Sung-Jun/Getty Images)