People make pictures in a Soviet-era vintage subway car, with a Soviet railways emblem on the side of it, parked in the Partizanskaya subway station in Moscow, Russia, Friday, May 15, 2015. Vintage Soviet-era metro cars were exhibited at the Partizanskaya subway station as part of festivities marking the 80th anniversary of the Moscow subway on Friday. (Photo by Pavel Golovkin/AP Photo)

An actress performs in a puppet theater show at an UNRWA school in Burj al-Barajneh in Beirut May 14, 2015. The Arab Puppet Theatre Foundation (APTF) is touring the 68 schools of the UN refugee agency's UNRWA and performs for all 39,000 Palestinian students in Lebanon, in a project with UNICEF and UNRWA. (Photo by Mohamed Azakir/Reuters)

A Western Lowland Gorilla baby named “Mjukuu”, that was born in October last year, rides on the back of its Mother “Mbeli” in their enclosure at Taronga Zoo in Sydney, Australia, May 19, 2015. The baby gorilla was born six days ago, and is the second sired by the zoo's new Silverback, Kibali, who arrived from France in 2012. (Photo by David Gray/Reuters)

Women walk next to soldiers in Surcubamba, Peru, Thursday, May 21, 2015. The Joint Command of the Peruvian Armed Forces organized a humanitarian mission to Surcubamba, where health care was provided to families from nearby villages in this region called VRAEM, the acronym for Valley of the Apurimac, Ene and Mantaro rivers, where sixty percent of Peru's cocaine originates. (Photo by Rodrigo Abd/AP Photo)

A girl is seen in a bakery in the old walled town of Harar in eastern Ethiopia, May 19, 2015. Daily life of people in Ethiopia, where elections are held this weekend, is portrayed in the east African nation's churches and mosques, coffee shops and markets, both in the capital Addis Ababa and the walled town of Harar in the east. Ethiopia, home to nearly 100 million people, holds the first poll on Sunday since long-serving leader Meles Zenawi died in 2012. (Photo by Siegfried Modola/Reuters)

The Virgin of El Rocio is carried by pilgrims during a procession around the shrine of El Rocio in Almonte, southern Spain, May 25, 2015. Every spring hundreds of thousands of devotees converge at a shrine to pay homage to the Virgin del Rocio during an annual pilgrimage which combines religious fervour and festive colour. (Photo by Marcelo del Pozo/Reuters)

A Nepalese boy gets ready to perform a stick dance during a rally held to pay tribute to the victims of an earthquake, in Bhaktapur, Nepal, Wednesday, September 2, 2015. Two powerful earthquakes in April and May devastated the Himalayan nation killing more than 8,800 people. (Photo by Niranjan Shrestha/AP Photo)

Model Heidi Klum in front of Concorde jet after arriving for Victoria's Secret fashion show at Cannes Film Festival on May 16, 2000. (Photo by Marion Curtis/DMI/The LIFE Picture Collection/Getty Images)