A rescue worker holds an injured boy after what activists said were airstrikes carried out by the Russian air force in Idlib city, Syria December 20, 2015. (Photo by Ammar Abdullah/Reuters)

Fighters of the pro-government Popular Resistance Committees militia carry a cannon as they transport it in parts to Yemen's southwestern war-torn city of Taiz December 26, 2015. (Photo by Reuters/Stringer)

A Palestinian throws snow at his wife during a snow storm in West Bank old city of Hebron, January 26, 2016. (Photo by Mussa Qawasma/Reuters)

A Palestinian reveller takes part in a colours festival organized by Palestinian activists in the West Bank city of Ramallah August 20, 2015. The festival is inspired by the Hindu spring festival of Holi. (Photo by Mohamad Torokman/Reuters)

Model Lily Donaldson flashes the peace sign as she leaves Victoria's Secret Fashion Show China casting in New York City on August 22, 2017. (Photo by Christopher Peterson/Splash News and Pictures)

Traffic enforcer Ramiro Hinojas, 51, wears a Santa Claus costume while directing motorists through traffic at an intersection in Pasay City, Metro Manila, Philippines on November 28, 2017. (Photo by Romeo Ranoco/Reuters)

(L-R) Playmate Victoria Silvstedt, Donald Trump and Melania Knauss at the Playboy 50th Anniversary celebration December 4, 2003 in New York City. (Photo by Peter Kramer/Getty Images)

Beyonce and Jay-Z leave Rihanna's 3rd Annual Diamond Ball at Cipriani Wall Street on September 14, 2017 in New York City. (Photo by James Devaney/GC Images)