Demonstrators perform a dance in front of riot policemen during a march called by students to request changes in the education system in Santiago, Chile September 5, 2017. (Photo by Ivan Alvarado/Reuters)

A South Sudanese People Liberation Army (SPLA) soldier patrols the streets in Malakal on January 21, 2014. (Photo by Harrison Ngethi/AFP Photo)

Chinese aids activists hand out condoms in a subway train in Wuhan, central China's Hubei province on December 1, 2014. The World Health Organization issued a call to action to China on December 1, 2014 over HIV/AIDS as government figures said nearly half a million people are living with the disease or its precursor, with hundreds of thousands more thought to be undiagnosed. (Photo by AFP Photo)

Costumed characters participate in the 30th annual Dragon Con Parade in Atlanta, Georgia, USA, 03 September 2016. Thousands of attendees crowd downtown Atlanta hotels and streets during the Labor Day weekend for the Dragon Con science fiction and fantasy convention, many dressed as their favorite characters. (Photo by Erik S. Lesser/EPA)

A man passes a poster depicting French presidential election candidate for the far-right Front National (FN) party Marine Le Pen with the face of U.S. President Donald Trump reading “Do not Trump yourself. Choose France. Vote!” on May 5, 2017 in Paris. (Photo by Joel Saget/AFP Photo)

Sjinkie Knegt of Netherlands, left, and Park Se-Yeong of South Korea crash out as they compete in a men's 1500m short track speedskating final at the Iceberg Skating Palace during the 2014 Winter Olympics, Monday, February 10, 2014, in Sochi, Russia. (Photo by Bernat Armangue/AP Photo)

Max Gold, 20, of NYC, cruises on his skateboard as thousands gather on the National Mall for the March for Science on Saturday, April 22, 2017, in Washington, DC. Activists and scientists descend on the nation's capital to rally for environmental causes and government policies rooted in scientific research as part of the Earth Day and March for Science rallies. (Photo by Jahi Chikwendiu/The Washington Post)

Erika Kinsey of Sweden reacts after missing a jump in the women's high jump final during the IAAF World Indoor Athletics Championships in Portland, Oregon March 20, 2016. (Photo by Mike Blake/Reuters)