Wounded people walk after clashes with riot police in central Kiev February 18, 2014. Ukrainian riot police advanced on the heart of 12-week-old protests against President Viktor Yanukovich on Tuesday and security forces set a deadline to end disturbances after at least five protesters were reported killed in a day of clashes. (Photo by Vlad Sode/Reuters)

Bottlenose dolphins swim over visitors in water tank at the Hakkeijima Sea Paradise aquarium-amusement park complex in Yokohama, southwest of Tokyo, Tuesday, July 21, 2015. Temperatures in Tokyo's metropolitan area neared around 96 degree Fahrenheit, or 35 degree Celsius, on Tuesday. (Photo by Shuji Kajiyama/AP Photo)

Cosplayer Monzerath Gutierrez, who portrays Dragon Ball Z character Trunks, female version, poses for a portrait during the 4th edition of the MiniCon Anime convention, at the School of Dance, in Managua, Nicaragua, Sunday, July, 26, 2015. (Photo by Esteban Felix/AP Photo)

Arrow sports his new elastic booties at a PetSmart in Tempe, Ariz. on Tuesday, June 20, 2017. Phoenix radio station KSLX handed out the protective coverings to protect dogs' paws from the hot pavement, as temperatures in Phoenix are forecasted to hit 120 degrees (48°C). (Photo by Angie Wang/AP Photo)

Dancers perform “El torito”, during a celebration honoring Saint Thomas, the patron saint of Chichicastenango, Guatemala, Saturday, December 21, 2019. The Feast of Saint Thomas draws international tourists with its colorful pageantry, but at its heart is a religious celebration melding Catholic and indigenous traditions that culminates on Dec. 21. (Photo by Moises Castillo/AP Photo)

Elderly women wait for customers as they sell their self-made food products at a street market, with a graffiti depicting Russian President Vladimir Putin on the wall of a house seen in the background, in the town of Kashira, outside Moscow, Russia on October 10, 2017. (Photo by Andrey Volkov/Reuters)

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)

A model presents a creation at a metro station during a show opening the Moscow Fashion Week in Moscow, Russia on October 22, 2019. (Photo by Evgenia Novozhenina/Reuters)