Performers take part in a procession as part of the Samhuinn Fire Festival on October 31, 2024 in Edinburgh, Scotland. The Samhuinn Fire Festival is a modern take on an ancient Celtic festival, marking the transition between summer and winter with fire-dancing, drums, acrobatics, and theatre performances. (Photo by Jeff J. Mitchell/Getty Images)

Arnold Schwarzenegger gives a thumbs up as he arrives for the Europe premiere of his new movie 'Terminator: Genisys' in Berlin, Germany, Sunday, June 21, 2015. (AP Photo/Michael Sohn)

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

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)

The Photographers 2015 runs from 25 November to 23 December at Osborne Samuel and Beetles+Huxley, London. Here: Untitled, 1950, by Bert Hardy. (Photo by Bert Hardy/Beetles+Huxley & Osborne Samuel)

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)

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