Ten-year-old Macy Friday, front left, reacts as she looks back at her family after meeting Hillary Clinton, front right, as she campaigns for U.S. Sen. Mark Udall, D-Colo., back, during a stop in the newly-renovated Union Station in Denver on Monday, October 13, 2014. Clinton appeared at an event to raise money for Udall's current re-election campaign and then headed to Las Vegas for another appearance on Monday night. (Photo by David Zalubowski/AP Photo)

West Berliners crowd in front of the Berlin Wall as they watch East German border guards demolish a section of the wall on November 11, 1989. (Photo by Gerard Malie/AFP Photo)

Shoppers wrestle over a television as they compete to purchase retail items on “Black Friday” at an Asda superstore in Wembley, north London November 28, 2014. Britain's high streets, malls and online sites were awash with discounts on Friday as more retailers than ever embraced U.S.-style “Black Friday” promotions, seeking to kickstart trading in the key Christmas period. In the United States the Friday following the Thanksgiving Day holiday is called Black Friday because spending usually surges and indicates the point at which American retailers begin to turn a profit for the year, or go “into the black”. (Photo by Luke MacGregor/Reuters)

A Yemeni soldier, pictured through a vehicle's windscreen, which was damaged by a bullet, gestures out of the window, in Marib, Yemen October 15, 2015. Marib is a city that is heavily armed even by the standards of Yemen, where the ready availability of weapons helped start civil war and is now preventing anyone coming out on top. Yemenis often say there are three guns for every person, a boast that has become an urgent concern in a country where the United Nations says the humanitarian situation is "critical". (Photo by Angus McDowall/Reuters)

Two novice Buddhist monks walk alongside a basket seller to collect alms following a clerics rule of no footwear nor use of umbrellas in Mandalay, Myanmar, Friday, October 9, 2015. (Photo by Hkun Lat/AP Photo)

People stand around a leopard with its head stuck in a vessel in Rajsamand district of Rajasthan state, India, Wednesday, September 30, 2015. The leopard's head got stuck when it attempted to drink water from the pot, according to news reports. Forest officials tranquilized the animal and sawed off the vessel later in the day. (Photo by Kabir Jethi/AP Photo)

An Indian cyclist pedals with a child during heavy rain in Mumbai, Maharashtra state, India, Friday, July 24, 2015. Several parts of the city witnessed heavy rain Friday. The monsoon rains which usually hit India from June to September are crucial for farmers whose crops feed hundreds of millions of people. (Photo by Rajanish Kakade/AP Photo)

Waura Indians wrestle during this year's “quarup”, a ritual held over several days to honour in death a person of great importance to them, in Xingu National Park, Mato Grosso State, Brazil August 25, 2013. (Photo by Ueslei Marcelino/Reuters)