Students celebrate their A-level results at King Edward VI High School for Girls in Birmingham, England on August 18, 2016. The proportion of top grades achieved by A-level students across the UK has fallen for a fifth year in a row, and girls have caught up with boys in attaining A* grades. (Photo by Joe Giddens/PA Wire)

In a photo taken on June 5, 2017 a traffic security officer stands on duty at an intersection in Pyongyang. Officially known as traffic security officers but universally referred to as traffic ladies, they are chosen for their looks in a society that remains traditionalist in many respects. They must leave the role if they marry, and have a finite shelf-life, with compulsory retirement looming at just 26. (Photo by Ed Jones/AFP Photo)

Demonstrators clash with members of the Bolivarian National Police as protests continue in Caracas, Venezuela, 20 April 2017. The Bolivarian National Guard, using tear gas, tried to disperse protests against the government of Venezuelan President Nicolas Maduro. (Photo by Miguel Gutierrez/EPA)

Amish girls play softball after class during an end of the school year celebration on Tuesday, April 9, 2013 in Bergholz, Ohio. The celebration was also part of a farewell picnic for four women and one man from this tight-knit group in rural eastern Ohio who will enter prison on Friday, April 12, joining nine already behind bars on hate crimes convictions for hair- and beard-cutting attacks against fellow Amish. (Photo by Scott R. Galvin/AP Photo)

Lightning from a tornadic thunderstorm passing over Clearwater, Kansas strikes at an open field May 19, 2013. A massive storm front swept north through the central United States on Sunday, hammering the region with fist-sized hail, blinding rain and tornadoes, including a half-mile wide twister that struck near Oklahoma City. News reports said at least one person had died. (Photo by Gene Blevins/Reuters)

Seized plastic handguns which were created using 3D printing technology are displayed at Kanagawa police station in Yokohama, south of Tokyo, in this photo taken by Kyodo May 8, 2014. Yoshimoto Imura became the first man to be arrested in Japan for illegal possession of two guns he created himself using 3D printing technology, Japanese media said on Thursday. The 27-year-old, a college employee in the city of Kawasaki, was arrested after police found video online posted by Imura claiming to have produced his own guns. Gun possession is strictly regulated in Japan. Police raided Imura's home and found five guns, two of which could fire real bullets, Japanese media said. (Photo by Reuters/Kyodo)

These are the stomach-churning pictures of the swing at the end of the world – a rickety wooden swing hanging over a precipice 2,660 metres above sea level – and not a seatbelt in sight. (Photo by Caters News)

Young Slovaks dressed in traditional costumes throw a bucket of water at a girl as part of Easter celebrations in the village of Trencianska Tepla, Slovakia, April 9, 2012. Slovakia's men splash women with water to symbolize youth, strength and beauty for the upcoming spring season. (Photo by Samuel Kubani/AFP)