Kimono-clad women enjoy the view from Tokyo Sky Tree’s 350-meter-high observation deck in Sumida Ward, Tokyo, on the Coming of Age Day, January 9, 2017. Sumida Ward invited about 430 local 20-year-old to the deck to celebrate them. Many city governments invite local 20-years-old to there’s symbolic places and celebrate for their Coming of Age Day. (Photo by The Yomiuri Shimbun via AP Images)

This picture taken on October 20, 2016 shows students practising wushu at the Tagou martial arts school in Dengfeng. China is investing hugely in football training and has vowed to have 50 million school- age players by 2020, as the ruling Communist party eyes “football superpower” status by 2050. (Photo by Nicolas Asfouri/AFP Photo)

A visitor jumps for a photograph on the world's highest and longest glass-bottomed bridge above a valley in Zhangjiajie in China's Hunan Province on August 21, 2016. The bridge, which opened to the public on a trial basis on Saturday, spans 430 meters (1,410 feet) and rises about 300 meters (984 feet) above a valley in a scenic zone, making it the world's highest and longest glass-bottomed bridge according to Chinese state media. (Photo by Fred Dufour/AFP Photo)

Humanoid robots compete in a group match of the 20th RoboCup in Leipzig, Germany, June 30, 2016. About 3,500 participants from 45 countries and regions compete in the robot world championship until 04 July. (Photo by Sebastian Willnow/EPA)

Costumed revelers pose in front of the Chapell bridge on the opening day of the carnival in Lucerne, Switzerland, 20 February 20​20. The carnival takes place in Lucerne from 20 to 25 February 2020. (Photo by Alexandra Wey/EPA/EFE)

A couple sunbath on the beach in Ostrowo, northern Poland, July 20, 2015. Picture taken July 20, 2015. (Photo by Kacper Pempel/Reuters)

A woman smokes marijuana during the annual 4/20 marijuana rally on Parliament Hill in Ottawa, Ontario, Canada, April 20, 2017. (Photo by Chris Wattie/Reuters)

In this photograph taken on January 29, 2017, Afghan members of a wushu martial arts group led by trainer Sima Azimi (C), 20, pose for a photograph at the Shahrak Haji Nabi hilltop overlooking Kabul. Afghanistan's first female wushu trainer, Sima Azimi, 20, is training 20 Afghan girls aged between 14 – 20 at a wushu club in Kabul, after learning the sport while living as a refugee in Iran. (Photo by Wakil Kohsar/AFP Photo)