An Afghan boy jumps off the turret of a Soviet tank on a hilltop on the the outskirts of Kabul, Sunday, March, 4, 2018. (Photo by Rahmat Gul/AP Photo)

In this photo taken Friday, September 4, 2015, tourists Sarah and John Scott from Worcester, England, take a step back as a male silverback mountain gorilla from the family of mountain gorillas named Amahoro, which means “peace” in the Rwandan language, unexpectedly steps out from the bush to cross their path in the dense forest on the slopes of Mount Bisoke volcano in Volcanoes National Park, northern Rwanda. Deep in Rwanda's steep-sloped forest, increasing numbers of tourists are heading to see the mountain gorillas, a subspecies whose total population is an estimated 900 and who also live in neighboring Uganda and Congo, fueling an industry seen as key to the welfare of the critically endangered species as well as Rwanda's economy. (Photo by Ben Curtis/AP Photo)

Young girls attend a training session in MGFSO Olympic reserve school in Moscow on May 30, 2016. (Photo by Kirill Kudryavtsev/AFP Photo)

Ostriches wear masks as they are transported by a truck for relocation in Zhengzhou, Henan Province, China, August 8, 2016. (Photo by Reuters/Stringer)

A pedestrian carries an umbrella as they stroll past an advertisment as a rainstorm moves through Sacramento, Calif., Wednesday, February 13, 2019. Rain is falling widely in Northern California and is expected to spread south. (Photo by Rich Pedroncelli/AP Photo)

Syrian refugee boys play with toy guns at Eminonu district in Istanbul, Turkey, 08 January 2019. (Photo by Sedat Suna/EPA/EFE)

Sun Rongchun, 57, exercises with an improvised cervical traction device attached to a high bar at a sports complex in Shenyang, Liaoning province, China on April 9, 2019. (Photo by Sheng Li/Reuters)

Evangelia Platanioti of Greece competes in the Solo Technical Routine at the Glasgow 2018 European Synchronised Swimming Championships, Glasgow, Britain, 06 August 2018. (Photo by Neil Hall/EPA/EFE)