Students walk to school on the first day of their new school year in Giza, south of Cairo, Egypt September 25, 2016. (Photo by Mohamed Abd El Ghany/Reuters)

A girl plays on a pile of discarded flowers outside a market, the day after the Diwali celebrations in Mumbai, India October 31, 2016. (Photo by Shailesh Andrade/Reuters)

Laura Giombini of Italy reacts during the Women's Beach Volleyball preliminary round Pool D match against Jamie Lynn Broder and Kristina Valjas of Canada on Day 2 of the Rio 2016 Olympic Games at the Beach Volleyball Arena on August 7, 2016 in Rio de Janeiro, Brazil. (Photo by Shaun Botterill/Getty Images)

Members of the 3rd U.S. Infantry Regiment place American flags at the graves of U.S. soldiers buried at Arlington National Cemetery in preparation for Memorial Day May 26, 2011 in Arlington, Virginia. “Flags-In” has become an annual event since the 3rd U.S. Infantry Regiment (The Old Guard) was appointed an Army official ceremonial unit in 1948. Every available soldier in the 3rd U.S. Infantry Regiment participates in these annual ceremonies. (Photo by Win McNamee/Getty Images)

Lance Corpral Johnnie Miller of the Household Cavalry rehearses at Floors Castle in preparation for massed Pipe Band day on August 26, 2011 in Kelso, Scotland. The event, being held on August 28, will feature the first Scottish performance of the Household Cavalry's Musical ride in over 10 years. (Photo by Jeff J Mitchell/Getty Images)

Members of the public view crosses in Scotland?s first Field of Remembrance in Princess Street Gardens on November 7, 2011 in Edinburgh, Scotland. Volunteers helped plant approximately 11,000 remembrance crosses as a temporary memorial to mark the 90th anniversary of the Scottish Poppy Appeal. (Photo by Jeff J Mitchell/Getty Images)

A model wearing a Maxime Rappaz design, winner of the Annabelle Award, walks the runway during the second day of the Charles Voegele Fashion Days on November 10, 2011 in Zurich, Switzerland. (Photo by The Image Gate/Getty Images for IMG)

Hardy Dutch swimmers brave the icy North Sea on January 1, 2012 in Scheveningen, Netherlands. A record number of 10,000 people took the plunge in this year's traditional New Year's dip. The high turnout was attributed to the mild weather with a sea temperature of 8 degrees compared to 4 degrees last year. (Photo by Jasper Juinen/Getty Images)