A hooded protester throws a petrol bomb to riot policemen during clashes, following a rally marking the 43rd anniversary of a 1973 student uprising against the military dictatorship that was ruling Greece, in Athens, Greece, November 17, 2016. (Photo by Yannis Behrakis/Reuters)

A mahout walks with an elephant after bathing him in a river, before taking part in an elephant festival, which organisers say aims to raise awareness about elephants, in Sayaboury province, Laos February 17, 2017. (Photo by Phoonsab Thevongsa/Reuters)

British model Jourdan Dunn arrives for the premiere of “The Killing of a Sacred Deer” during the 70th annual Cannes Film Festival, in Cannes, France, 22 May 2017. The movie is presented in the Official Competition of the festival which runs from 17 to 28 May. Dress by Elie Saab Haute Couture. (Photo by Julien Warnand/EPA)

Activists in a clay outfits at the Rathausmarkt during the art protest campaign “1000 Gestalten” (lit 1000 figures), for more solidarity and political participation, in Hamburg, Germany, 17 June 2017. In a two-hour show hundreds of actors took part in a creative public appeal for more humanity and self-responsibility ahead of the upcoming G20 summit. The G20 economic summit takes place in Hamburg July 7-8. (Photo by Lukas Barth-Tuttas/DPA/Alamy Live News)

This picture taken with an underwater camera shows Japan' s Yumi Adachi competing in the Mixed Duet technical final during the synchronised swimming competition at the 2017 FINA World Championships in Budapest, on July 17, 2017. (Photo by Bernadett Szabo/Reuters)

Xiao Jiguo, a 29-year-old actor from China's Sichuan province, reacts after shaping his eyebrows to impersonate U.S. President Barack Obama in a hotel room in the southern Chinese city of Guangzhou September 17, 2015. Xiao is taking part in the filming of a comedy film in Guangzhou, playing a low-level gangster who looks like Obama. (Photo by Bobby Yip/Reuters)

Visitors walk past "Sculpture #1" by Darren Bader at the Frieze Art Fair in London, Britain October 14, 2015. The Frieze Art Fair, which is one of the world's leading contemporary art fairs, opens today and runs through October 17. (Photo by Suzanne Plunkett/Reuters)

People use snowshoes during a tour of the Great Kemeri Bog, Latvia, October 17, 2015. The Kemeri bog is more than 8,000 years old and is one of the largest dry moss swamps in the Baltics. A more than decade-long joint restoration of the bog by the European Union and the Latvian government helped the bog recover its high moss marshes, damp black alder forests, floodplain meadows and seaside lakes – features now considered rare in Europe due to industrialisation. (Photo by Ints Kalnins/Reuters)