Children, wearing red neckerchiefs, a symbol of the Pioneer Organization, salute during a ceremony for the inauguration of 18 new members at a local school in the southern settlement of Kazminskoye in Stavropol region, Russia, November 19, 2015. Early pro-communist youth movements, which appeared in Russia after the 1917 Bolshevik revolution, were reformed into the Pioneer Organization of the Soviet Union. While the organization lost its dominance among students in post-Soviet Russia, some educational institutions and families still carry on this tradition. (Photo by Eduard Korniyenko/Reuters)

Athletes in action during the international parachuting competition Mountain Gravity in Quinto, Switzerland, 27 August 2015. Some 200 participants from all over the world are expected to jump at the event running from 22 to 30 August 2015. (Photo by Samuel Golay/EPA)

In this Thursday, May 8, 2014 photo, guests look down from the Tilt!, a new tourist attraction that provides guests a unique view of the downtown area from the 94th floor of the John Hancock Building, after it was unveiled in Chicago. People hold onto handrails as the glass and steel facade tilts forward 30 degrees. (Photo by Ashlee Rezin/AP Photo/Sun-Times Media)

Two biplanes of the Team Breitling cross during a training flight prior the AIR14 air show in Payerne, Switzerland, August 29, 2014. (Photo by Peter Schneider/EPA)

Russian soldiers from 34th motorized infantry mountain brigade, 58th Army, prepare to evacuate a fellow soldier acting as an injured person during a drill at the Darial range outside Russia's city of Vladikavkaz, July 28, 2010. (Photo by Kazbek Basayev/Reuters)

Employee Jenny Forgie works on an orchid display at Kew Gardens in London, Thursday, February 8, 2018. The 23rd annual Orchid Festival is the first one with a Thailand theme, 66 volunteers worked on the 6,950 exhibited orchids. The festival is open from Feb. 10, 2018 until March 11, 2018. (Photo by Frank Augstein/AP Photo)

A Palestinian worker carries stalks at a sugar cane farm in the southern Gaza Strip city of Khan Yunis, on October 19, 2020. (Photo by Said Khatib/AFP Photo)