Festivalgoers watch two actors of the Wasteland Warriors movement fight in a cage at the world's largest heavy metal festival, the Wacken Open Air 2019, in Wacken, Germany on August 3, 2019. Wacken is a village in northern Germany with a population of 1,800 that has hosted the annual festival, which attracts heavy metal fans from around the world, since 1990. (Photo by Wolfgang Rattay/Reuters)

A family tries to cross a flooded road amid gushing water in Kolkata, India on August 17, 2019. Heavy rain continues for a second day in Kolkata, which contuinued to flood many streets all around the city. Authorities are working overtime to clear the roads. (Photo by Debarchan Chatterjee/Zuma Wire/Rex Features/Shutterstock)

Prince Dudeman stands on Ryan Thor's head at the 14th annual Helen Woodward Animal Center “Surf-A-Thon” where more than 70 dogs competed in five different weight classes for “Top Surf Dog 2019” in Del Mar, California, U.S., September 8, 2019. (Photo by Mike Blake/Reuters)

Actress Ella Balinska attends a Charlie's Angels VIP Screening Hosted by Elizabeth Banks and Natalie Zfat, in Partnership with Harry & David at AMC Empire 25 on November 05, 2019 in New York City. (Photo by Ben Gabbe/Getty Images for Sony Pictures)

Migrants, part of a caravan traveling en route to the United States, carry an anteater that was hit by a car, according to them, as they walk on the road that links Arriaga and Tapanatepec, near Arriaga, Mexico, November 5, 2018. (Photo by Carlos Garcia Rawlins/Reuters)

Street artist Irony’s mural of a young woman on Jamaica Street in Liverpool, UK on September 22, 2019. The city has recently been transformed with bold murals painted by local artists on walls and buildings. Recognisable faces including those of the Beatles, Jürgen Klopp and Stephen Hawking. (Photo by Peter Byrne/PA Wire Press Association)

Fifty years ago, as France exploded in mass protests, words scrawled on the walls of the Sorbonne summed up the revolutionary zeal of the time: “Run free, comrade, we’ve left the old world behind!”. Sexual liberation, artistic creativity and anti-capitalism were the order of the day. For those who were there, it was an unforgettable time. Here: A wounded student is transported by first-aid workers during riots on the Boulevard Saint-Michel, Paris, France on May 6, 1968. (Photo by Gökşin Sipahioğlu/SIPA Press)

Cha Huilan, a 40-year old Lisu woman, and her daughter leave Lazimi village with a zipline across the Nu River in Nujiang Lisu Autonomous Prefecture in Yunnan province, China, March 24, 2018. Chinese mountain villagers, cut off from shops and churches by a raging river, use a zipline to cross its violent rapids and jagged rocks. (Photo by Aly Song/Reuters)