A child walks to an installation made from fallen leaves by college students, in shape of a sofa, to call for people's attention to environment protection, in Hangzhou, Zhejiang province, China, December 6, 2016. (Photo by Reuters/China Daily)

An unidentified runner gestures while being attended by medical services following the first running of the bulls of the San Fermin festival in Pamplona, northern Spain, July 7, 2015. Two runners were gored in the run that lasted 2 minutes and 23 seconds, according to local media. (Photo by Eloy Alonso/Reuters)

Russia's synchronised swimming duet Aleksandr Maltsev (L) and Darina Valitova compete in the Mixed Duet Technical preliminary during the synchronised swimming competition at the 2015 FINA World Championships in Kazan on July 25, 2015. (Photo by Christophe Simon/AFP Photo)

Steam emerges from a cooling tower of the nuclear power plant Leibstadt near Leibstadt, Switzerland, November 18, 2014. (Photo by Arnd Wiegmann/Reuters)

A boy jumps into a pool of mud during the traditional “Bloco da Lama” or “Mud Street” carnival party, in Paraty, Brazil, Saturday, February 25, 2017. Legend has it the “bloco” was born in 1986 after local teens hiking in a nearby mangrove forest smeared themselves with mud to discourage mosquitoes and then wandered through Paraty. The party grew year after year, but revelers eventually were banned from parading in the colonial downtown after shopkeepers complained pristine white walls were stained with the hard-to-remove mud. (Photo by Mauro Pimentel/AP Photo)

The Pink Floyd inflatable pig floats next to Broadcasting House to promote their new exhibition at the V&A museum, in London, Britain May 10, 2017. (Photo by Neil Hall/Reuters)

A man pours water on his camel on a hot summer day in Ahmedabad, India, May 18, 2017. (Photo by Amit Dave/Reuters)

Bathers brave the cold waters of the North Sea as they take part in the annual Boxing Day dip at Redcar Beach on December 26, 2019 in Redcar, England. The event attracts hundreds of people each year who take to the cold water wearing fancy dress as they help to raise money for a number of charities. (Photo by James Glossop/The Times)