People in funny costumes race down the slope in bathtubs during the 7th Bathtub race at Stoos, Switzerland, on January 19, 2019. (Photo by Urs Flueeler/EPA/EFE/Rex Features/Shutterstock)

2016 Rio Olympics, Swimming, Preliminary, Men's 100m Backstroke, Heats, Olympic Aquatics Stadium, Rio de Janeiro, Brazil on August 7 2016. Christopher Reid (RSA) of South Africa competes. (Photo by Dominic Ebenbichler/Reuters)

A tank rolls out from a ship on a landing operation during military drills at the Black Sea coast, Crimea, Friday, September 9, 2016. Russia has deployed cruise missiles, multiple rocket launchers, tanks and its latest anti-aircraft system at massive military drills in Crimea. The drills which began across southern Russia and Crimea earlier this week and involve over 120,000 troops are some of the largest exercises Russia has held for years. (Photo by Pavel Golovkin/AP Photo)

Seized plastic handguns which were created using 3D printing technology are displayed at Kanagawa police station in Yokohama, south of Tokyo, in this photo taken by Kyodo May 8, 2014. Yoshimoto Imura became the first man to be arrested in Japan for illegal possession of two guns he created himself using 3D printing technology, Japanese media said on Thursday. The 27-year-old, a college employee in the city of Kawasaki, was arrested after police found video online posted by Imura claiming to have produced his own guns. Gun possession is strictly regulated in Japan. Police raided Imura's home and found five guns, two of which could fire real bullets, Japanese media said. (Photo by Reuters/Kyodo)

Unwanted phones recreated as interactive birds, part of “Escape III” by Anthony Goh and Neil Mendoza seen on display at the Barbican's Digital Revolution exhibition on July 2, 2014 in London, England. The exhibition brings together artists, designers, film makers, musicians and architects who push the boundaries of creativity that digitial technology can offer, and runs from July 3 until September 14, 2014. (Photo by Matthew Lloyd/Getty Images for Barbican Art Gallery)

In this Thursday, February 14, 2019, photo, a Transformer's Bumblebee mascot helps a woman carries paper bags at a shopping mall in Handan in north China's Hebei province. U.S. and Chinese envoys are holding a second day of trade talks after the top economic adviser to President Donald Trump said he has yet to decide whether to go ahead with a March 2 tariff increase on imports from China. (Photo by Chinatopix via AP Photo)

A fan gestures next to a police officer while celebrating the life of British singer Keith Flint of techno group “The Prodigy” after his funeral in Braintree, Essex, Britain, March 29, 2019. (Photo by Henry Nicholls/Reuters)

A member of the Revolutionary Armed Forces of Colombia (FARC) pose for a picture at a camp in the Colombian mountains on February 2005. (Photo by Frank Piasecki Poulsen)