A visitor stands in front of a portrait taken by artist Bruce Gilden at the “Masters of Photography” exhibition at the Photokina trade fair in Cologne on September 20, 2016. The fair for the photographic and imaging sector, that is running from September 20 to 25, 2016, presents products from image capture, image processing and storage to image output. Photokina also includes a program of events with congresses, workshops, symposiums and photography exhibitions. (Photo by Patrik Stollarz/AFP Photo)

A man carries a bag on his back in Guangzhou, Guangdong province, January 26, 2016. According to traffic police, over 2.9 billion trips will be made around China during the 40-day Spring Festival travel rush, which started on January 24. (Photo by Reuters/Stringer)

A bus goes through a flooded area in Jiujiang, Jiangxi Province, China, June 19, 2016. A week of torrential rain in southern China has killed dozens of people and forced relocation of tens of thousands of residents, media reported. (Photo by Reuters/China Daily)

A vintage military aircraft is seen parked ahead of the International Air and Space Fair (FIDAE) at the Arturo Merino Benitez international airport in Santiago, Chile March 29, 2016. (Photo by Rodrigo Garrido/Reuters)

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)

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