People walk through crop circles in a cornfield near Raisting, Germany, on July 28, 2014. According to media reports, a balloonist had discovered the circle some days ago. Since then, hundreds of people came to the field to watch it, however it is unclear who did create the pattern. (Photo by Karl-Josef Hildenbrand/DPA)

In this photo taken Saturday, June 20, 2015, Mahmoud Abdulnabi tries out an oud, an Arabic instrument related to the lute, at his workshop in Baghdad, Iraq. “The oud is different than other musical instruments”, said Abdulnabi, who has crafted ouds played by some of Iraq's best known musicians, many of whom look down from headshots on the walls. “If you feel joyful, it can play your joy. If the circumstances are sad it can play your sorrow and... help to empty whatever is in your chest”. (Photo by Hadi Mizban/AP Photo)

Topless activist Kaila J. walks through the rain following a “Free the Nipple” demonstration in Hampton Beach, New Hampshire August 23, 2015. (Photo by Brian Snyder/Reuters)

Sarah Bui poses for photographer, Brian Le around blossoming cherry trees, near the Tidal Basin on Thursday March 23, 2017 in Washington, DC. (Photo by Matt McClain/The Washington Post)

Armed forces veteran Frank Simpson at the Portico library being camouflaged by body artist Carolyn Roper in Manchester, UK on May 16, 2016 as part of the #CountThemIn campaign launched on Monday by the Royal British Legion. (Photo by Jon Super/Royal British Legion/PA Wire)

A man pushes her daughter on a cart as they shop at a market in Seoul, South Korea, July 26, 2016. (Photo by Kim Hong-Ji/Reuters)

Runners sleep before competing in the 2016 New York City Marathon in the Manhattan borough of New York City, NY, U.S. November 6, 2016. (Photo by Eduardo Munoz/Reuters)

A boy sits on the back of a crocodile on May 19, 2018 at a pond in Bazoule in Burkina Faso, a village which happily shares its local pond with “sacred” crocodiles. Crocodiles may be one of the deadliest hunters in the animal kingdom, but in a small village in Burkina Faso it is not unusual to see someone sitting atop one of the fearsome reptiles. According to local legend, the startling relationship with the predators dates back to at least the 15 th century. The village was in the grip of an agonising drought until the crocodiles led women to a hidden pond where the population could slake their thirst. (Photo by Olympia de Maismont/AFP Photo)