Balloons are inflated at the Bristol International balloon fiesta in south west England August 6, 2015. Now in its 37th year, the Bristol International Balloon Fiesta is Europe's largest annual hot air balloon event in the city that is seen by many balloonists as the home of modern ballooning. (Photo by Toby Melville/Reuters)

Carnival revellers pose during the postponed “Rosenmontag” (Rose Monday) parade in Mainz, Germany, May 8, 2016, after the original parade in February was cancelled due to severe weather. (Photo by Ralph Orlowski/Reuters)

A staff member (R) looks on next to a cake, which was baked in the shape of a muscular man, for customers to try for free during a promotional event of a cake store in Shenyang, Liaoning province, China, December 6, 2015. (Photo by Reuters/Stringer)

Passengers wear no trousers as they ride the London Underground in London, Britain, 07 January 2018. The No Pants Subway Ride is an global annual event where people take the public transport while they are not wearing trousers to surprise other passengers. This event takes place on the first Sunday of every year in the world's major cities. (Photo by Tolga Akmen/EPA/EFE/Rex Features/Shutterstock)

Two friends take a quick selfie during the Grand National Festival at Aintree Racecourse on April 6, 2017 in Liverpool, England. (Photo by WENN)

A baby dives as his mother holds on tightly during a water baby class in Odessa, Ukraine on August 6, 2016. (Photo by Andrey Nekrasov/Barcroft Images)

A tourist stands on the shore of a private beach in Naama Bay, Sharm el-Sheikh, south Sinai, Egypt, Sunday, November 8, 2015. Britain's foreign secretary says airport security in many cities will need to be overhauled if it is confirmed the Russian plane crash in the Sinai was caused by a bomb planted by the Islamic State group or someone inspired by the militants. (Photo by Vinciane Jacquet/AP Photo)

Russian police cadets march during general rehearsal of the Victory Day parade on the Dvortsovaya Square in St. Petersburg, Russia, 07 May 2021. The military parade marking the 76th anniversary of the victory over Nazi Germany in the World War II will take place on the Dvortsovaya Square on 09 May 2021. (Photo by Anatoly Maltsev/EPA/EFE)