The Boeoegg, a giant symbolic snowman made of wadding and and filled with firecrackers burns on top of a bonfire in Sechselaeuten square on April 24, 2017 in Zurich. When the bells of the Saint Peter's church chime six o'clock, the bonfire under the snowman is set in fire and the guildsmen wearing historical costumes ride around the bonfire. The faster the head of the snowman explods the warmer and more beautiful the summer will be. (Photo by Michael Buholzer/AFP Photo)

A ballet dancer attends a photo shooting as activists from the environmentalist group Greenpeace unfurl a giant banner on the Eiffel Tower which reads “Liberty, Equality, Fraternity” in a call on French citizens to vote against the National Front (FN) presidential candidate Marine Le Pen, in Paris, France May 5, 2017. (Photo by Gonzalo Fuentes/Reuters)

South Korean students pose for a selfie following a traditional coming-of-age ceremony at Namsan hanok village in Seoul on May 15, 2017. The Coming of Age Day is the day to celebrate and encourage the youth who have reached the age of 20, which is considered the beginning of adulthood. (Photo by Ed Jones/AFP Photo)

A photo taken on July 22, 2017 shows beach- goers dancing at the West Sea Barrage beach outside the coastal city of Nampo, southwest of Pyongyang. The West Sea Barrage beach features as a stopping point for foreign tourists, and is a destination for North Korean work groups from the neighbouring area. The beach lies at the end of an eight- kilometre- long barrage that separates the sea from the Taedong River, which runs through Pyongyang. (Photo by Ed Jones/AFP Photo)

People affected by Hurricane Maria bathe in water piped from a creek in the mountains, in Naranjito, Puerto Rico, Thursday, September 28, 2017. Residents of the area drive to the pipes to bathe because they were left without water supplies by the damage caused by Hurricane Maria. The pipe was set up by a neighbor who ran it from a creek in his property to the side of the road in order to help those left without water. (Photo by Ramon Espinosa/AP Photo)

Gremio fans celebrate after their team won the Copa Libertadores final match at the Arena do Gremio in Porto Alegre, Brazil on November 29, 2017. (Photo by Diego Vara/Reuters)

US President Donald Trump and First Lady Melania Trump watch the Florida Atlantic University Marching Band and cheerleaders perform prior to a Super Bowl party at Trump International Golf Club in West Palm Beach, Florida, February 4, 2018. (Photo by Saul Loeb/AFP Photo)

People with a South Korean flag waves as fireworks get off outside the stadium during the opening ceremony of the Pyeongchang 2018 Winter Olympic Games at the Pyeongchang Stadium on February 9, 2018. (Photo by Martin Bernetti/AFP Photo)