A man works inside a bakery in the rebel-controlled area of Maaret al-Numan town in Idlib province, Syria December 17, 2015. (Photo by Khalil Ashawi/Reuters)

A woman wearing a four-leaf clover-like hairpin takes a selfie nearby Nanluoguxiang street in Beijing, China, September 16, 2015. Wearing antenna styled hairpins in the shape of various flowers and plants at scenic spots has become a new trend in Beijing. (Photo by Kim Kyung-Hoon/Reuters)

An East German civilian (L) shows an East German customs officer the contents of his Trabant (auto) at checkpoint Potsdamer Platz in East Berlin in this November 24, 1989 file picture, as East Germany enforcing stringent customs controls to avoid smuggling. (Photo by Reuters)

A group of people are seen on a Victoria line train in London, England during the first night of the Night Tube service on August 19 2016. The Central line and Victoria line are the first to operate a Night service with further lines expected to be running by the end of the year. (Photo by SWNS.com)

Ostriches wear masks as they are transported by a truck for relocation in Zhengzhou, Henan Province, China, August 8, 2016. (Photo by Reuters/Stringer)

United States' Inika McPherson prepares an attempt during the women' s high jump final during the World Athletics Championships in London Saturday, August 12, 2017. (Photo by Kai Pfaffenbach/Reuters)

An elderly woman plays an accordion in Moscow, Russia on October 3, 2017. (Photo by Mladen Antonov/AFP Photo)

South Vietnamese forces escort suspected Viet Cong officer Nguyen Van Lem (also known as Bay Lop) on a Saigon street February 1, 1968, early in the Tet Offensive. Moments later, Lem was executed by Gen. Nguyen Ngoc Loan, chief of the national police. (Photo by Eddie Adams/AP Photo)