Girls sit inside an empty classroom as they pose for a photograph during a celebration marking the end of the school year in the town of Douma, eastern Ghouta in Damascus, Syria May 21, 2016. (Photo by Bassam Khabieh/Reuters)

Cardi B accepts the top rap song award for “I Like It” at the Billboard Music Awards on Wednesday, May 1, 2019, at the MGM Grand Garden Arena in Las Vegas. (Photo by Chris Pizzello/Invision/AP Photo)

A young woman takes pictures of the city with her mobile phone, from the glass-floor observation platform, in the Oriental Pearl Tower, in the financial district of Shanghai, on May 9, 2019. (Photo by Hector Retamal/AFP Photo)

An EF-2 tornado begins to rope out on the outskirts of Mangum, Oklahoma, U.S. on May 20, 2019. Multiple tornadoes touched down and heavy rain flooded areas across Oklahoma. (Photo by Brett Conner/ZUMA Wire)

Prime Minister Theresa May meets Russian President Vladimir Putin during the G20 summit in Osaka, Japan on June 28, 2019. (Photo by Stefan Rousseau/PA Images via Getty Images)

North Koreans perform during a mass game of “The Land of the People” at the May Day Stadium in Pyongyang, North Korea, Tuesday, June 25, 2019. (Photo by Jon Chol Jin/AP Photo)

A riot policeman fires into the air during clashes with opposition supporters at a rally demanding a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)

A pilgrim walks on her knees to fulfil her vows, as pilgrims attend the 99th anniversary of the appearance of the Virgin Mary to three shepherd children, at the Catholic shrine of Fatima, Portugal May 12, 2016. (Photo by Rafael Marchante/Reuters)