People board a train at the West Railway Station on January 7, 2012 in Beijing, China. China's railways are bracing themselves as millions of migrant labourers are set to leave cities for their native villages to celebrate the Chinese New Year. (Photo by Lintao Zhang/Getty Images)

A young girl plays on the glass bottom platform of the Oriental Pear TV Tower as she travels with her family on the second day of the Chinese Lunar New Year holiday, also known as Spring Festival, in Shanghai, China on February 18, 2018. Some 287 million tourists travelled in China during the first four days of the week-long Chinese Lunar New Year holiday, up 11.1 percent from the same period last year, new data showed Sunday. (Photo by Imaginechina/Rex Features/Shutterstock)

Residents carry a slaughtered pig with a bamboo pole as they walk home on a street, which was shut to traffic due to ice, in Leishan county, Guizhou province January 31, 2015. Blizzards and icy rain that lasted for several days at the end of January have disrupted traffic, collapsed houses and decimated crops in central Chinese provinces, Xinhua News Agency reported. (Photo by Reuters/Stringer)

People pass a suitcase as they line up to enter a railway station in Beijing, February 15, 2015. Chinese Ministry of Transport said a total of 2.807 billion trips are expected to be made during the 40-day Spring Festival travel rush, which started on February 4 and will last until March 16, Xinhua News Agency reported. (Photo by Reuters/Stringer)

A pro-democracy protester wearing a Guy Fawkes mask holds a yellow umbrella and a banner in the part of Hong Kong's financial central district protesters are occupying November 2, 2014. The former British colony of Hong Kong, which returned to Chinese rule in 1997, has witnessed a month of protests calling on the Beijing-backed government to keep its promise of introducing universal suffrage. The protests have for the most part been peaceful, with occasional clashes between the student-led protesters and Beijing supporters seeking to move them from the streets. (Photo by Damir Sagolj/Reuters)

This picture taken on November 1, 2014 shows Japanese body-painting artist Hikaru Cho (L) adding the finishing touches to a body painting of fingers sticking out from prison cell bars on the head of Ryonosuke Tanaka during “Tokyo Designers Week” in Tokyo. Cho, 21, was born to Chinese parents in Japan and burst onto Tokyo's art scene when she entered the city's Musashino Art University in 2012. Cho's ultimate ambition is to paint an entire – and naked – body. (Photo by Yoshikazu Tsuno/AFP Photo)

A flight attendant wearing a Brazil soccer team jersey demonstrates the emergency mask on an airplane travelling from Kunming to Hangzhou June 23, 2014. A Chinese airline company renovated the cabin of one of its flights then dressed the flight attendants with soccer jerseys as a way to celebrate the 2014 Brazil World Cup and hoping to attract more customers, local media reported. (Photo by Wong Campion/Reuters)

Chinese rescuers carry an injuried resident after an earthquake hit an area of Ludian county in Zhaotong in southwest China's Yunnan province on August 3, 2014. At least 300 people were killed and 1,300 injured after a strong earthquake hit southwest China's mountainous Yunnan province, state media said. The quake in Zhaotong prefecture, in the province's northeast, toppled buildings and left residents frantically searching for survivors beneath the rubble, images on social media showed. (Photo by AFP Photo)