A festival goer uses a hula hoop, as revelers gather ahead of this weekends Glastonbury Festival of Music and Performing Arts on Worthy Farm in Somerset, southwest England, on June 25, 2014. US metal giants Metallica will play this year's coveted Saturday night headline spot at Britain's Glastonbury festival, organisers announced Thursday. It will be the “Master of Puppets” four-piece's first appearance at the legendary festival, held in south west England, following on from The Rolling Stones' Worthy Farm debut last year. (Photo by Leon Neal/AFP Photo)

Students receive a group punishment during a military-style close-order drill class at the Qide Education Center in Beijing February 19, 2014. The Qide Education Center is a military-style boot camp which offers treatment for internet addiction. As growing numbers of young people in China immerse themselves in the cyber world, spending hours playing games online, worried parents are increasingly turning to boot camps to crush addiction. Military-style boot camps, designed to wean young people off their addiction to the internet, number as many as 250 in China alone. (Photo by Kim Kyung-Hoon/Reuters)

An employe of Russian Space Training Center hangs out to dry space suits of Russian cosmonaut Anatoly Ivanishin, NASA's U.S. flight engineer Kathleen Rubins, and Japanese space agency's flight engineer Takuya Onishi, right, after their undergoing training near in Noginsk, 60 km (38 miles) east of Moscow, Russia, Wednesday, July 2, 2014. The training was intended to simulate the capsule landing on water. Russian cosmonaut Anatoly Ivanishin, Japanese space agency's flight engineer Takuya Onishi, and NASA's U.S. flight engineer Kathleen Rubins are being trained for a future mission to the International Space Station. (Photo by Alexander Zemlianichenko/AP Photo)

Polar Bear club swimmers take their annual swim in the sea at Coney Island in New York City on January 1, 2014. (Photo by Curtis Means/ACE/INFphoto.com)

Meri Nirmala Sari, 11, poses in her traditional costume before a performance August 6, 2002 in Ubud, Bali, Indonesia. Meri dances with the Gunung Sari Peliatan dance group and has become a professional. She started dancing at age 5. (Photo by Paula Bronstein/Getty Images)

South Korean environmentalists participates in a rally held to commemorate the Fukushima nuclear disaster on the eve of the one year anniversary of Japan's earthquake and tsunami on March 10, 2012 in Seoul, South Korea. Currently four nuclear power plants are in operation in South Korea while the government plans to increase the number of reactors to 32 by the year 2021. (Photo by Chung Sung-Jun/Getty Images)

Vincent Yu is a multiple award winner who won Honorable Mention in the 2013 Photographer of the Year category for Pictures of the Year International. Photo: A statue of Hotei Buddha sits in the debris in the tsunami-destroyed town of Sendai, Miyagi Prefecture, northern Japan Friday, April 1, 2011. (Photo by Vincent Yu/AP Photo)

Jewish children in fancy dress during the annual Jewish holiday of Purim on March 12, 2017 in London, England. Purim is celebrated by Jewish communities around the world with parades and costume parties. Purim commemorates the defeat of Haman, the advisor to the Persian king, and his plot to massacre the Jewish people, 2,500 years ago, as recorded in the biblical book of Esther. (Photo by Dan Kitwood/Getty Images)