Soldiers of China's People's Liberation Army (PLA) jump as part of their winter training in temperature of negative 26 degrees Celsius at China's border with Russia in Heihe, Heilongjiang province, December 14, 2015. (Photo by Reuters/Stringer)

This picture taken on July 25, 2014 shows people cooling off in a waterpark in Suining, southwest China's Sichuan province. Meteorological departments issued an orange alert for high temperature as a heat wave embraces Sichuan province, with temperature of most area topped 37, local media reported. (Photo by AFP Photo)

A spectator cools herself at a water spraying fan at the Australian Open tennis championships in Melbourne, Australia, Tuesday, January 17, 2017. (Photo by Kin Cheung/AP Photo)

Athletes in action during the international parachuting competition Mountain Gravity in Quinto, Switzerland, 27 August 2015. Some 200 participants from all over the world are expected to jump at the event running from 22 to 30 August 2015. (Photo by Samuel Golay/EPA)

“T'antawawas” (children's bread) are displayed in a popular market to commemorate All Saints Day in La Paz, October 30, 2016. (Photo by David Mercado/Reuters)

In this April 14, 2018 photo, National Ballet of Cuba dancer Daniela Gomez Perez stands on point as she poses outside the Capitol in Havana, Cuba. Gomez, who says Cubans love dancing, trusts the next generation of leaders will continue such traditions and that art will continue to be the engine of Cuban society. Gomez said she is proud to represent Cuba during a dance trip in May to Washington, Tampa and Chicago, and that the Cuban state has always supported dance. (Photo by Ramon Espinosa/AP Photo)

An Iraqi shi'ite muslim girl places a copy of the Koran on her head during the holy month of Ramadan at the Imam Ali Shrine, in the holy city of Najaf, Iraq on May 28, 2019. (Photo by Alaa Al-Marjani/Reuters)

Children play underneath Jacaranda trees lining a street in the capital Harare, Zimbabwe, Friday, October 11, 2019. Zimbabwe now has the world's second highest inflation after Venezuela, according to International Monetary Fund figures. The economy has been on a downward spiral for more than a year as hopes fade that Mugabe's successor and former deputy, President Emmerson Mnangagwa, will deliver on his promises of prosperity. (Photo by Tsvangirayi Mukwazhi/AP Photo)