A donkey savors warming temperatures after a long winter at the zoo in Warsaw, Poland, on Wednesday, April 8, 2015. (Photo by Czarek Sokolowski/AP Photo)

In this timed-exposure night photo taken early on February 12, 2017, Mount Sinabung volcano spews reddish smoke and ash, as seen from the Karo district in North Sumatra province. Activity levels have increased in the past week, with Sinabung shooting hot ash clouds into the sky dozens of times, according to the local volcano monitoring agency. (Photo by AFP Photo/Stringer)

A boy looks on as fire fighters try to extinguish the fire at oil wells, were set on fire by Daesh terrorists as they fled after Al Qayyarah town's cleansing from Daesh militants as the operation to retake Iraq's Mosul from Daesh continues, in Al Qayyarah Town of Mosul, Nineveh, Iraq on November 02, 2016. (Photo by Yunus Keles/Anadolu Agency/Getty Images)

Russian cadet preparing before the International Kremlin Cadet Ball in Moscow, Russia 12 December 2017. More than 1500 students from all Russian cadets school attend in Cadet Ball. (Photo by Yuri Kochetkov/EPA/EFE)

A runner competes in the Great Wall Marathon at the Huangyaguan Great Wall outside Beijing, China, May 18, 2019. (Photo by Thomas Peter/Reuters)

Adolf Hitler (left), German Nazi politician, in a deck chair next to is niece Angela (Geli) Raubal – around 1930. (Photo by Ullstein Bild/Ullstein Bild via Getty Images)

Boxers Deontay Wilder, left, and Tyson Fury exchange words as they face each other at a news conference in Los Angeles, Wednesday, November 28, 2018. The pair are slated to fight Saturday night for Wilder's WBC heavyweight title. (Photo by Andrew Couldridge/Action Images via Reuters)

Los Angeles Rams cheerleaders including the first two male cheerleaders in Super Bowl history (C) perform in the third quarter of Super Bowl LIII between the New England Patriots and the Los Angeles Rams at Mercedes-Benz Stadium in Atlanta, Georgia, USA, 03 February 2019. (Photo by Mike Zarrilli/EPA/EFE)