A cultural dance group waits to perform at Gambela stadium during Ethiopia's Nations and Nationalities Festival in Gambela town, in Ethiopia December 8, 2015. Picture taken December 8, 2015. (Photo by Tiksa Negeri/Reuters)

Nepalese students of Himalayan agriculture college play in mud water in a paddy field to celebrate the National Paddy Day in Badegaun village, Lalitpur, Nepal, 29 June 2016. More than 100 students and teachers of Himalayan agriculture college participated in the National paddy day by planting rice and playing in mud water as Nepal is celebrating National Paddy Day with various event. (Photo by Narendra Shrestha/EPA)

Firefighters watch as an air tanker drops retardant while battling the Ferguson fire in the Stanislaus National Forest, near Yosemite National Park, California on July 21, 2018. A fire that claimed the life of one firefighter and injured two others near California's Yosemite national park has almost doubled in size in three days, authorities said Friday. (Photo by Noah Berger/AFP Photo)

Workers are pictured at a shisha manufacturing factory in Baghdad December 17, 2014. (Photo by Thaier Al-Sudani/Reuters)

A snowflake rests on black velvet after a snowfall in Knoxville on Tuesday, January 28, 2014. (Photo by Adam Lau/News Sentinel)

Paris Fashion Week, Spring/Summer 2014 Haute Couture collection by Charlie Le Mindu. (Photo by Yoan Valat/EPA)

A rugby fan adjusts his latex mask at the rugby sevens tournament in Hong Kong on March 29, 2014. (Photo by Philippe Lopez/AFP Photo)

View of a Spitfire from the cockpit of an He111,somewhere over Southern England 1941 – 2014. (Photo by Adam Surrey)