Danielle Collins of the US reacts to a point in the first set while playing Caroline Wozniacki of Denmark during Round Two Women's Singles tennis match of the 2019 US Open at the USTA Billie Jean King National Tennis Center in New York on August 29, 2019. (Photo by Robert Deutsch/USA TODAY Sports)

A mural on an apartment block created as part of the Urban Morphogenesis street art festival in the Novaya Tryokhgorka residential neighbourhood in the town of Odintsovo in Moscow Region, Russia on August 31, 2019. (Photo by Valery Sharifulin/TASS)

Protesters begin to gather ahead of the UK Student Climate Network's Global Climate Strike at Millbank in London, England on September 20, 2019. (Photo by Gareth Fuller/PA Images via Getty Images)

Scott Meiklejohn gets into character as a mummy during a photo call on October 10, 2019 in Stirling, Scotland ahead of “Hallowild”, Blair Drummond Safari Parks annual Halloween event. This years theme in the haunted walkway is an egyptian tomb with special 3D effects alongside actors playing the roles of Pharaohs and Mummies. (Photo by Andrew Milligan/PA Images via Getty Images)

Fisherman Jose Miguel Perez, whose nickname is “Taliban”, navigates the oil infested waters of Lake Maracaibo, near Cabimas, Venezuela, May 21, 2019. Nobody lives as closely with the environmental fallout of Venezuela's collapsing oil industry as the fishermen who scratch out an existence on the blackened, sticky shores of Lake Maracaibo. (Photo by Rodrigo Abd/AP Photo)

Kyrgyz dancers perform in an event gathering bedouins and nomads from around the world as part of the annual King Abdulaziz Camel Festival in Rumah desert, northeast of the Saudi capital Riyadh, on March 19, 2019. (Photo by Fayez Nureldine/AFP Photo)

In this Sunday, March 24, 2019, file photo, free skate pairs gold medalist Sui Wenjing and Han Cong of China perform during the gala exhibition for the ISU World Figure Skating Championships at Saitama Super Arena in Saitama, north of Tokyo. (Photo by Annice Lyn/AP Photo)

Anti-government protesters take cover during clashes with security forces who are firing tear gas from La Carlota airbase in Caracas, Venezuela, Wednesday, May 1, 2019. Opposition leader Juan Guaidó called for Venezuelans to fill streets around the country Wednesday to demand President Nicolás Maduro's ouster. Maduro is also calling for his supporters to rally. (Photo by Ariana Cubillos/AP Photo)