Pro-Russian rebels stand near a monument during a ceremony to honour the World War Two defenders of Donetsk from Nazi forces, in Donetsk, in this September 8, 2014 file photo. (Photo by Marko Djurica/Reuters)

Mount Sinabung volcano erupts, as seen from Tiga Pancur village, Karo Regency in Indonesia's North Sumatra province, in this October 8, 2014 file photo. (Photo by Y. T. Haryono/Reuters)

Lazar and his sister Andjelka sit by a candle in their home in the eastern Serbian town of Majdanpek, December 4, 2014. Electricity workers in Serbia struggled through snow, ice and treacherous terrain on Thursday to restore electricity to an eastern town left shivering without power, heating or running water for a fourth day. (Photo by Marko Djurica/Reuters)

Ary Borges feeds his tiger named Dan at his home in Maringa, Brazil, Thursday, September 26, 2013. Borges is in a legal battle with federal wildlife officials to keep his endangered animals from undergoing vasectomies and being taken away from him. He defends his right to breed the animals and says he gives them a better home than they might find elsewhere in Brazil. (Photo by Renata Brito/AP Photo)

Tommy Lindsey holds an enormous maple leaf that he found in Mount Vernon, Wash., October 28, 2013. Lindsey was walking with his family when he picked up the leaf that is more than two feet from stem to tip and more than 21 inches wide. (Photo by Frank Varga/The Skagit Valley Herald)

Western lowland gorilla Kijivu holds her newborn baby at the Prague Zoo in the Czech Republic. (Photo by Isifa/Getty Images)

A motorcycle-taxi driver takes a nap while leaning on his bike along a street in Bangkok, Thailand on February 17, 2019. (Photo by Jewel Samad/AFP Photo)

Skiers and snowboarders in swimwear during the Grelka Fest-2019 Festival at the Sheregesh ski resort, Kemerovo Region, Russia on April 13, 2019. (Photo by Kirill Kukhmar/TASS)