Employees work at a sorting centre of Zhongtong (ZTO) Express ahead of the Singles Day shopping festival, Chaoyang District, Beijing, November 8, 2015. On China's giant Singles Day internet shopping festival, the country's delivery firms are stretched so thin that they are looking for tie-ups, listings and new investors to husband their resources. (Photo by Jason Lee/Reuters)

Members of the Bavarian police and the Bundeswehr, the German armed forces, guard a vehicle checkpoint as they demonstrate a dynamic operation as part of the GETEX anti-terror exercises during a media event on March 9, 2017 in Murnau, Germany. (Photo by Philipp Guelland/Getty Images)

Women wearing sunglasses pose for a group photo at a park in Beijing in 1980. (Photo by Reuters/China Daily)

Monks take pictures with their mobile phones of the mummified body of a monk at Puzhao temple in Quanzhou, Fujian Province, China, January 10, 2016. According to local media, the monk named Fuhou died three years ago at the age of 94 and his remains was placed in a vat and turned into a mummy as a sign of respect. (Photo by Reuters/Stringer)

A rescuer saves a resident from a flooded area in Wuhan, Hubei Province, China, July 2, 2016. (Photo by Reuters/China Daily)

Local residents crowd a swimming pool during a hot weather in Suining, Sichuan province, 27 July 2008. (Photo by Reuters/Stringer)

A picture made available on 30 March 2016 shows members of the anti-terror squad of the local paramilitary force have a training in Suining, in southwest Sichuan province, China, 29 March 2016. (Photo by Zhong Min/EPA)

Members of the South Korean Special Weapons and Tactics team exhibit their skill during anti-terrorism exercises at a training camp on May 30, 2005 in Seoul, South Korea. (Photo by Chung Sung Jun/Getty Images)