A boy and a woman run across a railway track as a train approaches in Chengdu, Sichuan province, China, October 8, 2015. Many residents disregard sign prohibiting this kind of illegal crossing and choose to do so to save time, local media reported. (Photo by Hao Fei/Reuters/Western China Metropolis Daily)

Visitors walk past a train-shaped ice sculpture ahead of the 31st Harbin International Ice and Snow Festival in the northern city of Harbin, Heilongjiang province, January 4, 2015. The winter festival will be officially opened on January 5, 2015. (Photo by Kim Kyung-Hoon/Reuters)

Pakistani female police commandos attend a training session in Nowshera, near Peshawar Pakistan, Wednesday, February 11, 2015. Authorities formed a Special Combat Unit after Taliban militants stormed a Peshawar school on Dec. 16, 2014 and massacred 150 children and teachers. (Photo by Mohammad Sajjad/AP Photo)

North Korean leader Kim Jong Un smiles as he attends a flight training session by female fighter pilots Jo Kum Hyang and Rim Sol in this undated photo released by North Korea's Korean Central News Agency (KCNA) on June 22, 2015. (Photo by Reuters/KCNA/Antara Foto)

(L-R) Pieter Van Lankveld, Jay Schippers, Ynze Oegema, Justin Kimmann, Teun Kivit and Twan Van Gendt compete during the Dutch National BMX Championships at Olympic Training Centre Papendal on October 11, 2020 in Arnhem, Netherlands. (Photo by Dean Mouhtaropoulos/Getty Images)

Members of the special operations team conduct a building climbing training in Qinzhou, south China's Guangxi Zhuang Autonomous Region, April 13, 2021. (Photo credit should read Costfoto/Barcroft Media via Getty Images)

An Indian laborer talks on his mobile phone as he transports a refrigerator on his back at a market in Jammu, India, Sunday, June 7, 2020. India whose coronavirus caseload is fifth highest in the world has partially restored trains and domestic flights and allowed reopening of shops and manufacturing. (Photo by Channi Anand/AP Photo)

Visitors make snowmen beside a pool at a hot spring in Hangzhou, in China's eastern Zhejiang province on January 26, 2018. China's central and eastern regions have been hit by heavy snowfalls in recent days, causing disruptions to flight and train schedules. (Photo by AFP Photo/China Stringer Network)