A child plays with a soap bubble on the city hall plaza on March 14, 2015 in Paris. (Photo by Dominique Faget/AFP Photo)

Paul, 9, dumps a bucket of water over his head at a fountain near government buildings during hot weather on July 1, 2015 in Berlin, Germany. Temperatures across northern Europe are rising and in Germany a high of 36 degrees is forecast for the weekend. (Photo by Sean Gallup/Getty Images)

Katy Perry poses backstage during rehearsals for the 2017 MTV Video Music Awards at The Forum on August 25, 2017 in Inglewood, California. (Photo by John Shearer/Getty Images for MTV)

A young boy plays with soap bubbles near Hofburg Palace at Heldenplatz, one of the top tourists attractions in Vienna, Austria, January 26, 2016. (Photo by Christian Bruna/EPA)

Palestinian bedouin shepherds pull their lambs into the water to wash them, in Gaza City, on April 29, 2016. Every year before the beginning of the summer, shepherds wash their herds in the sea. (Photo by Mohammed Abed/AFP Photo)

Two brave contestants take part in the World Gravy Wrestling Championships at the Rose 'n Bowl in Stacksteads, Lancashire, England on August 27 2018. Contestants must wrestle in the gravy for 2 minutes, points are scored for fancy dress, comedy effect, entertainment and wrestling ability. The event is held to raise funds for the East Lancashire Hospice and competitors nominated charities. (Photo by The Mercury Press)

Picture dated October 23rd, 2018 shows brother and sister Henry (7) and Lily Sales (9) getting in some early practice for the World Puddle Jumping Championships at Wicksteed Park in Kettering, Northants, UK. Organisers have made more puddles than ever before in an attempt to make this year's competition the biggest and best yet. They are also hoping competitors will set a new record for the most people jumping in puddles at the same time. Judges will give scores based on the height of the jump, enthusiasm, distance of splash and stickability (the amount of mud which clings to each competitor). (Photo by Geoff Robinson Photography)

An American soldier walks ahead of an MKIV (Mark IV) British-made tank, circa 1918. (Photo by Hulton Archive/Getty Images)