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)

Habimana, 45, and her children walk to market to sell pottery on Idjwi island in the Democratic Republic of Congo, November 23, 2016. (Photo by Therese Di Campo/Reuters)

Participants of the annual “SlutWalk” march through the Israeli Mediterranean coastal city of Tel Aviv on May 4, 2018 to protest against rape culture, including sexual assault and harassment directed at women. The campaign, which has gained international notoriety, was inspired by group of Canadian women who launched the protest in 2011 in response to a policeman' s comment that if women want to avoid being attacked they should not dress like sl*ts. (Photo by Jack Guez/AFP Photo)

A protester gestures during a “Yellow vest” protest against higher fuel prices during clashes on the Champs-Elysees in Paris, France, November 24, 2018. (Photo by Benoit Tessier/Reuters)

Soldiers on exercise in Kenya. The image, by Sergeant Dek Traylor, is among the section winners in the UK Army Photographic Competition 2018. (Photo by Sergeant Dek Traylor/PA Wire Press Association)

Human canvases modelling world famous artworks including Van Gogh's Sunflowers and Edvard Munch's The Scream take to the streets of London in a bid to mend Britain's disconnect with art on September 25, 2017. Award winning body paint artist Sarah Attwell was commissioned by online art platform Rise Art to show that great art is for everybody, following research that revealed 1 in 6 Brits have never set foot in an art gallery. (Photo by Imagewise Ltd/Rex Features/Shutterstock)

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

Actor John Travolta (L) and recording artist Lady Gaga attend Interscope's Grammy After Party with Lady Gaga at the Peppermint Club on February 12, 2017 in Los Angeles, California. (Photo by Christopher Polk/Getty Images for Interscope)