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

Young contortionists practice at a training school in Ulaanbaatar, Mongolia, July 4, 2016. (Photo by Natalie Thomas/Reuters)

A tourist train is decorated with Christmas lights in Bogotá, Colombia on December 10, 2017. (Photo by Jaime Saldarriaga/Reuters)

Employees work on an electric train assembly line at the “Stadler Minsk” plant in Fanipol, Belarus February 10, 2016. (Photo by Vasily Fedosenko/Reuters)

Paramilitary policemen take part in a summer training in Shenzhen, Guangdong province, China, June 27, 2016. (Photo by Reuters/China Daily)

Paramilitary policemen take part in a training in Chaohu, Anhui province, China December 28, 2015. (Photo by Reuters/China Daily)

In a photo taken on October 7, 2020 a woman holds two dogs as she waits for a train in Suncheon. (Photo by Ed Jones/AFP Photo)

A U.S. Marine leads training on a shooting range in France in an undated photo taken during the First World War. (Photo by Reuters/Courtesy Library of Congress)