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 model walks the runway during the Di$count Universe show at Mercedes-Benz Fashion Week Resort 17 Collections at Carriageworks on May 18, 2016 in Sydney, Australia. (Photo by Stefan Gosatti/Getty Images)

Jean-Pierre Giagnoli walks through a crowded area of vendors hawking cat related goods at CatCon LA in Los Angeles, on Sunday, June 26, 2016. (Photo by Richard Vogel/AP Photo)

Mongolian President Tsakhiagiin Elbegdorj (C) walks towards the media after casting his vote for the parliamentary elections at a polling station in Ulaanbaatar, Mongolia, June 29, 2016. (Photo by Jason Lee/Reuters)

A man walks past a stranded public transport bus on a road flooded by heavy rains in Mumbai, India, August 5, 2016. (Photo by Shailesh Andrade/Reuters)

African migrants stranded in Costa Rica walk near garbage on the Inter-American highway at the border between Costa Rica and Nicaragua, in Penas Blancas, Costa Rica, September 8, 2016. (Photo by Juan Carlos Ulate/Reuters)

A model walks the runway during the Versace show as part of Paris Fashion Week Haute Couture Spring/Summer 2015 on January 25, 2015 in Paris, France. (Photo by Pascal Le Segretain/Getty Images)

Subway passengers walk past bronze sculptures representing the Soviet people at the Ploshchad Revolyutsii metro station in Moscow, on November 14, 2012. The station was opened in 1938. (Photo by Kirill Kudryavtsev/AFP Photo)