A Syria Democratic Forces (SDF) fighter comforts a civilian who was evacuated with others by the SDF from an Islamic State-controlled neighbourhood of Manbij, in Aleppo Governorate, Syria, August 12, 2016. The SDF has said Islamic State was using civilians as human shields. (Photo by Rodi Said/Reuters)

Tube passengers take a selfie next to a London underground roundel designed for the launching of the Night Tubes on display at Oxford Circus underground station in London, Britain, 19 August 2016. The long delayed Night Tubes service launched on 19 August. The 24-hour service will operate on Fridays and Saturdays. (Photo by Hannah Mckay/EPA)

A South Korean model poses with Peugeot 5008GT during a press preview of the Seoul Motor Show in Goyang, northwest of Seoul, on March 30, 2017. South Korea's largest international auto show will open on March 31, with a total of 27 brands showing their latest cars and concepts. (Photo by Jung Yeon-Je/AFP Photo)

Students participate in a wet t-shirt contest at the MTV Beach Bash party put on by Global Groove at the Bahia Mar Hotel during the annual ritual of Spring Break March 26, 2008 on South Padre Island, Texas. The South Texas island is one of the top Spring Break destinations and attracts students from all over the country. (Photo by Rick Gershon/Getty Images)

An injured supporter of Ivory Coast's Laurent Gbagbo reacts outside the premises of Hotel Golf, where Gbagbo is currently being held after his arrest, in Abidjan April 11, 2011. The trial of Laurent Gbagbo on charges of crimes against humanity during post-election violence, in which around 3,000 people were killed, will begin on January 28, 2016 at the International Criminal Court. (Photo by Reuters/Stringer)

Runner English Gardner poses for a portrait at the U.S. Olympic Committee Media Summit in Beverly Hills, Los Angeles, California March 8, 2016. “My musical inspiration when I'm training is usually a lot of upbeat music”, said Gardner. (Photo by Lucy Nicholson/Reuters)

Artists watch burning an effigy of Lady Maslenitsa as they celebrate Maslenitsa, or Pancake Week, in Baikonur, Kazakhstan, March 13, 2016. Maslenitsa is widely viewed as a pagan holiday marking the end of winter and is celebrated with pancake eating and shows of strength, while the Orthodox Church considers it as the week of feasting before Lent. (Photo by Shamil Zhumatov/Reuters)

19 giant panda cubs, all born this year, meet the public at the Shenshuping Base of the China Conservation and Research Centre for the Giant Panda on October 13, 2017 in Ngawa Tibetan and Qiang Autonomous Prefecture, China. So far China Conservation and Research Centre for the Giant Panda has successfully bred 42 giant pandas this year. (Photo by VCG/VCG via Getty Images)