A student aims a stick of wood at Bolivarian National Police officers during clashes outside the Central University in Caracas, Venezuela, Thursday, June 9, 2016. Students had planned to march from Venezuela's top university to elections headquarters, but hundreds of police in riot gear blocked the way. Students covered their faces with Venezuelan flags and threw bottles, stones and sticks while police lobbed tear gas. (Photo by Fernando Llano/AP Photo)

An injured vulture is treated at the VulPro Vulture Rehabilitation Centre in Hartebeepoortdam in the Magalisburg region on September 15, 2015. Confined to southern Africa, just under 4,000 breeding pairs of Cape Vultures remain in the wild, mostly in South Africa, Lesotho and Botswana. Unless conservation efforts are successful, Africa's largest vulture species may be facing eventual extinction. (Photo by Mujahid Safodien/AFP Photo)

A girl cover her face while riding a motorcycle as haze shrouds a street near Tanjung Siapi Api port in Palembang, on the Indonesian island of Sumatra, September 19, 2015. Indonesia will take 30 days to bring smouldering forest fires under control, the national disaster management agency said on Friday, as smog from the fires pushes pollution in Southeast Asia to record highs. (Photo by Reuters/Beawiharta)

An environmental activist adjusts his mask while taking part in “The Dead Sea Swim Challenge”, swimming from the Jordanian to Israeli shore, to draw attention to the ecological threats facing the Dead Sea, in Kibbutz Ein Gedi, Israel November 15, 2016. Swimmers from around the world plunged into the salty waters of the Dead Sea on Tuesday to attempt a seven-hour swim across the fabled lake in a bid to draw attention to its environmental degradation. Wearing protective masks and snorkels, 25 swimmers paddled through the muddy water to attempt the 9-mile (15-kilometer) swim from Jordan to Israel. (Photo by Nir Elias/Reuters)

A cadet from the Interior Ministry with the word Fidel painted on her face attends a rally honoring the late Cuban leader at the Revolution Plaza in Havana, Cuba, Tuesday, November 29, 2016. Schools and government offices were closed Tuesday for a second day of homage to Fidel Castro, with the day ending in a rally on the wide plaza where the Cuban leader delivered fiery speeches to mammoth crowds in the years after he seized power.Fidel Castro passed away Friday Nov. 25. He was 90. (Photo by Ramon Espinosa/AP Photo)

Hospitality staff are reflected in a puddle of water as they prepare to pose for photograph in front of a giant basket decorated with replicas of flowers and fruits on display on Tiananmen Square during the opening ceremony of the 19th Party Congress in Beijing, Wednesday, October 18, 2017. Chinese President Xi Jinping on Wednesday urged a reinvigorated Communist Party to take on a more forceful role in society and economic development to better address “grim” challenges facing the country as he opened a twice-a-decade national congress. (Photo by Andy Wong/AP Photo)

Three cabaret dancers sit glum-faced in the Windmill Theatre's canteen upon hearing the news that the theatre's owners have sold out to a cinema company, on October 02, 1964. The theatre, which was the first to include nudity in its shows, has been able to cope with competition from a growing number of West End strip clubs. (Photo by Hulton-Deutsch Collection/CORBIS/Corbis via Getty Images)

In this photo taken Monday, March 5, 2018, s*x worker Irene sits in her brothel in Juba, South Sudan. As World Women's Day is to be marked across the globe and women across much of the Western world have galvanized around the #MeToo movement, South Sudan remains a place where women face grinding difficulties and rights experts say most women remain voiceless. (Photo by AP Photo/Stringer)