Players perform during a game at the first Bubble Soccer tournament in Hitzkirch, near Lucerne, Switzerland, June 27, 2015. Bubble Soccer, also known as Zorb Soccer, is becoming increasingly popular around the world. The game is a recreation of playing soccer whilst encased in an inflated zorb which covers the players upper-body and head. (Photo by Urs Flueeler/EPA)

A child stands inside a large soap bubble made by a street artist at the Mayor square in central Madrid, Friday, December 9, 2016. (Photo by Francisco Seco/AP Photo)

Romanian military doctors and medical students sit on a bus behind steamy windows before the National Day parade in Bucharest, Romania, Thursday, December 1, 2016. Military planes and helicopters flew over the Romanian capital Thursday as thousands turned out to celebrate the national day, marking the date when the country reunified with Transylvania in 1918. (Photo by Vadim Ghirda/AP Photo)

Students exercise in body training at Bishan Vocational Education Center in Chongqing, southwest China, January 13, 2016. These students were trained to be stewardesses of the high-speed train. (Photo by Xie Jie/Xinhua)

A colorful sky at sunset over the snowy mountains in Immenstadt, Bavaria, Germany, 20 November 2014. Cloudy weather is forecast in the region on 21 November. (Photo by Karl-Josef Hildenbrand/EPA)

A boy jumps from a swing during sunset in Valras-Plage, southern France December 29, 2014. (Photo by Yves Herman/Reuters)

A woman reacts with flour over her face while playing a game with cake-making ingredients as part of local festivities marking Myanmar's 70th Independence Day in Yangon on January 4, 2018. The country is celebrating the 70th anniversary of its declaration of independence from British colonial rule. (Photo by Ye Aung Thu/AFP Photo)