Young people fight for fun with their pillows, during the International Pillow Fight Day at the Place des Grottes, in Geneva, Switzerland, Saturday, April 4, 2015. The annual International Pillow Fight Day takes place in hundreds of cities around the world. (Photo by Salvatore Di Nolfi/AP Photo/Keystone)

In this April 4, 2015, photo, Marilia Skraba, center, of Brazil, applies makeup while waiting to compete in the Miss Viva Las Vegas contest during the Viva Las Vegas Rockabilly Weekend in Las Vegas. The event draws thousands of people from around the world. (Photo by John Locher/AP Photo)

Visitors look at graffiti art created by Brazilian artist Image during the 3rd annual Graffiti Fine Art Biennial International exhibit, at the Pavilion of Brazilian Cultures, in Sao Paulo, Brazil, Tuesday, April 21, 2015. The month-long event features the work of more than 60 street artists, representing 11 countries. (Photo by Andre Penner/AP Photo)

A white Bengal tiger cub plays with its mother in a zoo in the Siberian city of Novosibirsk, about 2,800 kilometers (1,750 miles) east of Moscow, Russia, Tuesday, April 21, 2015. Two blue-eyed Bengal tiger cubs were born in March to a couple of white tigers at Novosibirsk zoo. (Photo by Ilnar Salakhiev/AP Photo)

Members of the Barrio 18 gang run upon their arrival to the San Francisco Gotera penitentiary April 21, 2015. The Salvadoran goverment transfered 1,177 inmates, members of the Barrio 18 gang from Izalco jail to San Francisco Gotera in a effort to curb gang violence activity, according to local media. (Photo by Jose Cabezas/Reuters)

A woman wearing a four-leaf clover-like hairpin takes a selfie nearby Nanluoguxiang street in Beijing, China, September 16, 2015. Wearing antenna styled hairpins in the shape of various flowers and plants at scenic spots has become a new trend in Beijing. (Photo by Kim Kyung-Hoon/Reuters)

Pedestrians and vehicles make their way past the Potala Palace early on a rainy morning in Lhasa, capital of the Tibet Autonomous Region in China, Saturday, September 19, 2015. Chinese officials have taken foreign journalists on a visit to the region, normally off-limits to them, weeks after Communist Party officials commemorated the 50th anniversary of the establishment of the Tibet Autonomous Region. (Photo by Aritz Parra/AP Photo)

Xiao Jiguo, a 29-year-old actor from China's Sichuan province, reacts after shaping his eyebrows to impersonate U.S. President Barack Obama in a hotel room in the southern Chinese city of Guangzhou September 17, 2015. Xiao is taking part in the filming of a comedy film in Guangzhou, playing a low-level gangster who looks like Obama. (Photo by Bobby Yip/Reuters)