In this Monday, July 24, 2017 photo, a police officer walks in front of a mural during a protest demanding an end to the current pension fund system, in Santiago, Chile. Protesters say the government pension system robs retirees of fair pension payments, and are demanding a new social security system with higher payments. (Photo by Esteban Felix/AP Photo)

Indian young men wearing traditional folk dance “Bhangra” attire of Punjab, sit on see-saws and sip on soft drinks at a park before their performance during the Khalsa College International Folk Festival 2017 in Amritsar, India, 29 November 2017. The festival is aimed to promote cultural ties between India and participating countries. (Photo by Raminder Pal Singh/EPA/EFE)

A man who was set on fire by people accusing him of stealing during a rally against Venezuela's President Nicolas Maduro runs amidst opposition supporters in Caracas, Venezuela, May 20, 2017. (Photo by Marco Bello/Reuters)

An unidentified elderly woman, who was knocked over during the melee after a shot was fired in the direction of President Ford, is comforted by a passerby in San Francisco, September 23, 1975. (Photo by AP Photo)

Gloria Grahame in state of undress in a scene from the film “Naked Alibi”, 1954. (Photo by Universal/Getty Images)

Filipino villagers escape to a safe area as the Mayon Volcano erupts anew in the town of Daraga, Albay province, Philippines, 23 January 2018. The Philippine Institute of Volcanology and Seismology (PHIVOLCS) agency on 22 January raised the alert level for the Mayon Volcano amid fears of a bigger eruption over the next few hours or days. (Photo by Francis R. Malasig/EPA/EFE)

Young children at a Bristol, Great Britain health centre unsure of the benefits of sun-lamps and the special glasses that must be worn, July 1948. The health centre was part of the newly introduced free National Health Service. (Photo by Popperfoto/Getty Images)

Participants compete in the Mud Day Race extreme run competition at El Goloso military base, outside Madrid, Spain, June 11, 2016. Thousands of athletes got covered in mud as they celebrated International Mud Day running a 13-kilometer obstacle course on a sunny Saturday with heatwave-like temperatures up to a 29 degrees Celcius (around 84 degrees Fahrenheit). (Photo by Juan Medina/Reuters)