A reveller from Unidos da Tijuca samba school performs during the second night of the carnival parade at the Sambadrome in Rio de Janeiro, Brazil, February 28, 2017. (Photo by Ricardo Moraes/Reuters)

A U.S. Army B-24 Liberator Bomber is hailed by a ground crewman as it takes off over a line of shark- nosed fighter planes at an advanced base in China on a mission on October 10, 1943, to bomb Japanese installations. (Photo by AP Photo)

Athletes vie for the ball during the Mud Olympics in Brunsbuettel, Germany, 30 July 2016. Since 2004, amateur athletes have been competing in various events at the mouth of the Elbe river on the North Sea. The proceeds are traditionally donated to the Schleswig-Holstein Cancer Society. (Photo by Daniel Bockwoldt/EPA)

South Korea's Shim Sukhee falls in the women's 1,500m short track speed skating heat event during the Pyeongchang 2018 Winter Olympic Games, at the Gangneung Ice Arena in Gangneung on February 17, 2018. (Photo by Mladen Antonov/AFP Photo)

A sculpture is displayed at the Olympic Sculptures Exhibition at the Sculpture Park September 4, 2006 in Changchun of Jilin Province, China. (Photo by China Photos/Getty Images)

A girl reacts as she is tattooed during the third International Tattoo Week Rio 2016 festival in Rio de Janeiro, Brazil, January 22, 2016. (Photo by Pilar Olivares/Reuters)

Syrian Tulin Hashemi waits for a job interview at a hotel in Vidigal slum in Rio de Janeiro, Brazil, September 22, 2015. Tulin, whose mother arrived two days ago, has been living in Brazil for two months. As she does not speak Portuguese, Tulin says it is difficult for her to find a job and therefore she is staying at the slum as it is one of the cheaper neighbourhoods to live in. According to the National Committee for Refugees (CONARE), 2,077 people fleeing the Syrian civil war have settled in Brazil, whilst a quarter of the 8,400 refugees in the Latin American country come from Syria. (Photo by Pilar Olivares/Reuters)

Estonia's olympic team female marathon runners triplets (L-R) Lily, Liina and Leila Luik run during a training session in Tartu, Estonia, May 26, 2016. Leila, Liina and Lily Luik will make Olympics history as the first identical triplets to compete against each other when they cross the start line for the women's marathon in Rio. (Photo by Ints Kalnins/Reuters)