A Chinese snake charmer performs at a temple fair to mark Chinese New Year February 19, 2007 in Beijing, China. Chinese worldwide are celebrating the Chinese Lunar New Year of the Pig. (Photo by Guang Niu/Getty Images)

Yan Mengjie sits on a boat as she poses for photos near Erhai Lake in Dali Bai Autonomous Prefecture, Yunnan province, China on June 16, 2019. Erhai is one of China's biggest freshwater lakes and a backdrop to the city of Dali, which drew 47 million visitors last year, more than triple the number in 2010. Hotels and homestays have sprung up along a 31-mile (50-km) stretch of lakeside road to accommodate tourists. But officials ordered some hotels demolished after President Xi Jinping during a 2015 visit called for the lake to be protected. (Photo by Tingshu Wang/Reuters)

Children wearing uniforms hold toy guns during a military parade game on China's National Day, at Beyou World, a centre children where can experience different kinds of professions, in Beijing, October 1, 2015. (Photo by Reuters/Stringer)

A work by Chinese artist ROBBBB is seen on a wall in the ruins of a building in Beijing September 27, 2015. The 25-year-old artist in Beijing prefers to display his work on the walls of abandoned buildings, rather than a gallery. His artwork is mostly derived from photos of people he sees in the Chinese capital, anyone ranging from elderly people to construction workers. (Photo by Jason Lee/Reuters)

A driverless vehicle runs at Vanke's Building Research Centre testing area in Dongguan, south China's Guangdong province November 2, 2015. The country's largest property developer, China Vanke, is investing in its own robots to do certain jobs in the face of a labor shortage in the world's most populated country. This driverless car is among the robots that Vanke is aiming to bring in. (Photo by Tyrone Siu/Reuters)

Japan's Self-Defence Forces' women's personnel march during the annual SDF ceremony at Asaka Base, Japan, October 23, 2016. Some 40,00 troops, 280 military tanks and vehicles participated in the annual Japan's Self-Defense Forces parade. (Photo by Kim Kyung-Hoon/Reuters)

Military policemen try to open a path ahead for the funeral of 21-year-old Mohamed Adel, one of the army officers who died in yesterday's Sinai attacks, in Al-Kaliobeya, near Cairo, Egypt, July 2, 2015. Egypt launched air strikes on Islamist militant targets in the Sinai peninsula on Thursday, killing 23 fighters a day after the deadliest clashes in the region in years, security sources said. The sources said those killed had taken part in Wednesday's fighting in which 100 militants and 17 soldiers, including four officers, were killed, according to the army spokesman. (Photo by Mohamed Abd El Ghany/Reuters)

Pilots plan a flight manoeuvre with model aircraft at a military air base in Vasylkiv, Ukraine, August 3, 2016. (Photo by Gleb Garanich/Reuters)