A female sniper of the Syrian Democratic Forces (SDF) monitors the area during a celebration at the iconic Al- Naim square in Raqa on October 19, 2017, after retaking the city from Islamic State (IS) group fighters. The SDF fighters flushed jihadist holdouts from Raqa' s main hospital and municipal stadium, wrapping up a more than four- month offensive against what used to be the inner sanctum of IS' s self- proclaimed “caliphate”. (Photo by Bulent Kilic/AFP Photo)

The Lake of Lights at Talkin Tarn lake near Brampton in Cumbria, England on October 22, 2017 – where hundreds of lights in the surrounding woodland represent a cherished memory of a relative friend or loved one no longer with us. (Photo by Owen Humphreys/PA Images via Getty Images)

Yippie leader Jerry Rubin, barred on December 4, from House Un-American Activities subcommittee hearing, aims a toy gun in “self defense” outside the Washington hearing room on December 5, 1969. Rubin showed up in his Santa Clause suit because he believed it was typical of the committee which, he said, “is a total circus”. (Photo by Bob Daugherty/AP Photo)

A follower of the Afro-Brazilian religion Umbanda pays tribute for Iemanja, goddess of the sea, in Copacabana Beach in Rio de Janeiro, Brazil December 29, 2017. Hundreds of practitioners of Brazil's Afro-Brazilian Candomble and Umbanda faiths have gathered at Rio de Janeiro's Copacabana beach to honor Yemanja. Worshippers were mostly dressed in white as they launched their offerings to Iemanja: small boats with flowers and bowls with candles and fruits. (Photo by Ricardo Moraes/Reuters)

North Korean cheerleaders arrive at a rest stop, or service station, as their bus convoy carrying a 280- member delegation on its way to the 2018 Pyeongchang winter Olympic games, makes its way past Gapyeong on February 7, 2018 More than 200 young North Korean women arrived in South Korea to root for athletes from both sides of the peninsula at the Winter Olympics. (Photo by Ed Jones/AFP Photo)

Leslie Cliff and his wife Violet, English figure skating pair. Olympic games of Garmisch-Partenkirchen (Germany), 1936. (Photo by Roger Viollet Collection/Getty Images)

Hotel ushers pose for a photo at Tiananmen Square as delegates attend the second plenary session of the National People's Congress (NPC) in Beijing, China, March 9, 2018. The CPPCC is the top advisory body of the Chinese political system and runs alongside the annual plenary meetings of the 13th National People's Congress (NPC), together known as “Lianghui” or “Two Meetings”. (Photo by Jason Lee/Reuters)

Syrian civil defence volunteers, known as the White Helmets, rescue a boy from the rubble following a reported barrel bomb attack on the Bab al- Nairab neighbourhood of the northern Syrian city of Aleppo on November 24, 2016. (Photo by Ameer Alhalbi/AFP Photo)