A reveller is photographed during a traditional Maracatu carnival in Olinda, Brazil February 8, 2016. (Photo by Ueslei Marcelino/Reuters)

Employees cover bacon on fried dranik, a potato pancake that is the national dish of Belarus, in the Sula History Park near the village of Sula, Belarus March 7, 2016. According to the park's representatives, the two-metre-wide pancake was an attempt to enter the Guinness World Records as the world's largest dranik. (Photo by Vasily Fedosenko/Reuters)

A herdsman stands on the back of a grey bull during a ceremony of driving sheep from their winter habitat to their summer pasture in the puszta or Hungarian steppe of Hortobagy, 183 kms east of Budapest, Hungary, 23 April 2016. Sheep are traditionally driven to their summer pasture at around St. George's Day in the Hortobagy region, because livestock breeding people traditionally consider St. George's Day the beginning of spring. (Photo by Zsolt Czegledi/EPA)

A girl pours water over a dog to cool it down, in the rebel held besieged town of Douma, eastern Damascus suburb of Ghouta, Syria, June 23, 2016. (Photo by Bassam Khabieh/Reuters)

New York City, 1974. (Photo by Elliott Erwitt/Harry Ransom Center Collection/Magnum Photos)

Laura Paipo (L), first blind principal in Uruguay participates in a street race with her sighted guide and friend Amparo Bauter in Montevideo, October 4, 2015. Paipo, 55, who took office on August 10, 2015 became the first blind principal of a special school which specializes in the education of visually impaired students. (Photo by Andres Stapff/Reuters)

A girl reacts as she receives polio vaccine drops during a house-to-house vaccination campaign in Yemen's capital Sanaa, November 10, 2015. (Photo by Khaled Abdullah/Reuters)

German KUKA Robotics' robot LBR iiwa demonstrates a flower arrangement at the International Robot exhibition in Tokyo, Wednesday, December 2, 2015. (Photo by Shizuo Kambayashi/AP Photo)