Gymnast Valeria Kurochkina from Yekaterinburg performs during the Circus of Our Childhood festival at the Yekaterinburg Circus in Yekaterinburg, Russia on December 7, 2019. The festival marks the centenary of establishing state circuses in Russia. (Photo by Donat Sorokin/TASS)

Some of London's telephone operators and engineers, trying out their gas masks at the anti-gas civilian training centre in Gloucester, where they were taught how to deal with gas attacks. (Photo by Harry Todd/Fox Photos/Getty Images). 13th February 1937

Peter Ver Ploeg carries Virginia Petrovek through the mud pit during the North American Wife Carrying Championship, Saturday, October 8, 2016, at the Sunday River Ski Resort in Newry, Maine. (Photo by Robert F. Bukaty/AP Photo)

Revellers take part in the Notting Hill Carnival in London, Britain on August 27, 2018. The carnival has been held every year since 1966 and one of the largest festival celebrations of its kind in Europe. (Photo by Henry Nicholls/Reuters)

An unidentified elderly woman, who was knocked over during the melee after a shot was fired in the direction of President Ford, is comforted by a passerby in San Francisco, September 23, 1975. (Photo by AP Photo)

A photo taken by a member of the County Durham and Darlington fire and rescue Service of a coach on fire on the A1 in County Durham, England on March 2, 2017. Passengers were evacuated safely before flames engulfed the vehicle. (Photo by County Durham and Darlington Fir/PA Wire)

8-year-old Fulani boy Suleiman Yusuf drinks milk from a cow belonging to his father cattle near his family's house at Kachia Grazing Reserve, Kaduna State, Nigeria, on April 16, 2019. Kachia Grazing Reserve is an area set aside for the use of Fulani pastoralist and it is intended to be the foci of livestock development. The purpose for the grazing reserves is the settlement of nomadic pastoralists and inducement to sedentarisation through the provision of land for grazing and permanent water as way to avoid conflict. (Photo by Luis Tato/AFP Photo)

Bangladeshi people walk in a polluted air environment in Dhaka, Bangladesh on September 3, 2020. A study says, air pollution shortens life expectancy by seven years in Bangladesh. (Photo by Sultan Mahmud Mukut/SOPA Images/Rex Features/Shutterstock)