Secondary school graduates play in a fountain as they celebrate the last day of school, traditionally called the “last bell” in central Kiev, Ukraine on May 31, 2019. (Photo by Valentyn Ogirenko/Reuters)

An Indian man stands near his house as waves caused by high tide hits the huts on the shore of the Arabian Sea in Mumbai, India, Wednesday, July 3, 2019. Heavy monsoon rains in Maharashtra have led to more than 30 deaths since Monday night, from collapsed walls, drownings and other causes. Dozens of others have been injured. (Photo by Rafiq Maqbool/AP Photo)

A child covered in mud on Lake Chokrak near the village of Kurortnoye, Leninsky District of Crimea in Russia on July 4, 2019. (Photo by Sergei Malgavko/TASS)

Alien-themed decorations are seen at the Alien Research Center in Hiko, September 19, 2019. Scores of UFO enthusiasts converged on rural Nevada for a pilgrimage of sorts to the U.S. installation known as Area 51, long rumored to house government secrets about alien life, as law enforcement officials beefed up security around the military base. (Photo by Jim Urquhart/Reuters)

The Grevy’s Illusion by Yaron Schmid, USA: a Grevy’s zebra staring at the camera in Lewa, Kenya. Third place – wildlife. (Photo by Yaron Schmid/The Nature Conservancy Global Photo Contest 2019)

A female police officer stands in the street during an anti-government protest in Santiago, Chile, Saturday, October 26, 2019. Chile has been facing days of unrest, triggered by a relatively minor increase in subway fares. The protests have shaken a nation noted for economic stability over the past decades, which has seen steadily declining poverty despite persistent high rates of inequality. (Photo by Rodrigo Abd/AP Photo)

A woman cries while being escorted by police officers during an anti-government protest in Santiago, Chile, 07 November 2019. A proposed increase in the price of metro fares sparked a series of anti-government protests that have left at least 20 people dead. The protestors are demanding improvements in the quality of healthcare, education and general distribution of wealth in Chile. (Photo by Orlando Barría/EPA/EFE)

Visitors wear shirts with an image of former Chinese leader Mao Zedong at the Shanghai World Expo site in Shanghai, May 2, 2010. (Photo by Aly Song/Reuters)