Hot air balloons fly over the sky in Chiang Mai province, northern Thailand, December 6, 2014. The two-day International Balloon festival 2014 featuring balloon pilots from Germany, Spain, Netherlands, Britain, and Czech Republic is held on December 06-07 2014 to celebrate Thai King Bhumibol Adulyadej's 87th birthday and also aimed to promote the tourism industry in Chiang Mai northern city. (Photo by Pongmanat Tasiri/EPA)

The Mercedes-Benz F015 Luxury in Motion autonomous concept car is shown on stage during the 2015 International Consumer Electronics Show (CES) in Las Vegas, Nevada January 5, 2015. (Photo by Steve Marcus/Reuters)

American Yoga teacher Dashama poses on a Yoga-board during a preview of the 46th International Boat Fair in Duesseldorf January 16, 2015. The BOOT 2015 watersports fair, with more than 1,600 international exhibitors will run in Duesseldorf from January 17 to January 25. (Photo by Ina Fassbender/Reuters)

Aldi SugandaRizal (2 years-old) smoking a cigarette while playing at the family home in Sekayu district, South Sumatera, Indonesia on May 23, 2010. (Photo by Ardiles Rante/Barcroft Media)

A woman poses for a photographer (not pictured) as a man sits next to her in downtown Catania, Italy April 20, 2016. (Photo by Tony Gentile/Reuters)

A racegoer is given some water as he lays on the ground following 2017 Stakes Day at Flemington Racecourse on November 11, 2017 in Melbourne, Australia. (Photo by Scott Barbour/Getty Images)

A female member of Romania's military adjusts her hat before taking part in the national day military parade in Bucharest, Romania, Friday, December 1, 2017. Thousands of Romanian troops staged a military parade to celebrate Romania's national day, but key politicians didn't attend, signaling tensions between the president and the ruling left-wing coalition over plans to revamp the justice system. (Photo by Vadim Ghirda/AP Photo)

Tourists dressed in yukatas, a light, unlined, summer kimono made of cotton instead of the traditional silk, climb steps to visit a temple on April 27, 2016 in Kyoto, Japan. Now the seventh largest city in Japan, Kyoto was once the Imperial capital for more than one thousand years, it is now the capital city of Kyoto Prefecture and a major part of the Kyoto-Osaka-Kobe metropolitan area. (Photo by Carl Court/Getty Images)