Festival-goers wash on Shipyard Island, the venue of the 24th Sziget (Island) Festival in Northern Budapest, Hungary, 15 August 2016. The venue, one of the biggest cultural events of Europe, offers art exhibitions, theatrical and circus performances and above all music concerts from 10 to 17 August. (Photo by Szabó Gábor/Origo.hu)

Two models sit in an acrylic “ZF-Car” from the German manufacturer of the same name at the Automechanika automotive service industry trade fair in Frankfurt am Main, Germany, 12 September 2016. The Automechanika Fair runs from 13 to 17 September 2016. (Photo by Boris Rössler/EPA)

A street cleaner demonstrates his martial arts skills in front of a closed shop near Beijing's Tiananmen Square September 2, 2015 as the capital prepares for tomorrow's parade. (Photo by Damir Sagolj/Reuters)

Contorsionist Rich Miteku performs during the opening of the 41st Monte-Carlo International Circus Festival in Monaco on January 19, 2017. (Photo by Valery Hache/AFP Photo)

A painting of a Trabant car bursting through a wall in post unification Berlin, August 1993. (Photo by Steve Eason/Hulton Archive/Getty Images)

7th August 1941: A Soviet sniper targets the enemy with the telescopic sight on his rifle.

A Femen activist, Sarah Constantin, is hanged from a noose-like rope from a Paris bridge to call attention to the large number of executions in Iran as she stages a protest against visiting Iranian President Hassan Rouhani in Paris, Thursday, January 28, 2016. A near-naked woman hanging from a noose-like rope from a Paris bridge has sent a message to visiting Iranian President Hassan Rouhani. (Photo by Zacharie Scheurer/AP Photo)

A Sri Lankan leopard is pictured at a zoo in Dehiwala near Colombo on March 3, 2016, on World Wildlife Day. (Photo by Ishara S. Kodikara/AFP Photo)