A fighter of Libyan forces allied with the U.N.-backed government runs for cover during a battle with Islamic State fighters in Sirte, Libya, July 31, 2016. (Photo by Goran Tomasevic/Reuters)

A man climbs up a wooden pole to get a prize during celebration of Maslenitsa, or Pancake Week, a pagan holiday marking the end of winter, near Rumyantsevo, Moscow region, Russia, February 26, 2017. (Photo by Sergei Karpukhin/Reuters)

Cast member Shu Qi poses during a photocall for the film “The Assassin” (Nie yin niang) in competition at the 68th Cannes Film Festival in Cannes, southern France, May 21, 2015. (Photo by Eric Gaillard/Reuters)

In this September 10, 1977, file photo, from left, Hua Guofeng, Chinese Communist Party (CCP) chairman and Mao Zedong's immediate successor; Ye Jianying, CCP vice chairman and future ceremonial head of state; Deng Xiaoping, no formal titles at the time but soon to emerge as paramount leader during the reform era; Li Xiannian, CCP vice chairman and future president; Wang Dongxing, head of the leadership bodyguard unit who helped topple the Gang of Four, view the body of later Chinese leader Mao Zedong in Beijing. (Photo via AP Photo)

Paul Doherty of Australia with tatoo against Timothy Mareke of Solomon Island during the men's 75kg class at the Sydney International Invitation Boxing held at the Sydney Exhibition Centre, Darling Harbour, Sydney, Australia.

Street fighting in Berlin between Government troops and Spartacists, during the Spartacist uprising which followed Germany's defeat in World War I. (Photo by Keystone/Getty Images). 1919

Soldiers of the 70th division of the American 7th Army hold up a Nazi flag and a portrait of Adolf Hitler, taken during the World War II capture of Saarbrucken. (Photo by Horace Abrahams/Keystone/Getty Images). 22nd March 1945