Indonesian residents look at the Mount Sinabung volcano as it spews volcanic ash near the Tiga Pancur village in Karo, North Sumatra on August 3, 2016. Volcanic eruptions in Indonesia in recent days have forced the closure of two airports and disrupted some flights to the holiday island of Bali, officials said August 3. Mount Sinabung, a volcano on the western island of Sumatra which has been rumbling for some time, also erupted violently on August 2, although its ash clouds did not disrupt any flights. (Photo by Y.T. Haryono/AFP Photo)

Elementary school children play outside their classrooms as mount Sinabung volcano spews thick volcanic ash in the background on February 10, 2017 in Karo, Indonesia. Mount Sinabung is one of the most active volcanoes in Indonesia and last erupted in May 2016, killing seven people. (Photo by Albert Damanik/Barcroft Images)

The giant metal structure sits 330ft above the ground on the roof of a 22 storey office block in Dutch capital Amsterdam on September 6, 2016. Tourists sit in a playground-style chair as they propel themselves them over the edge of the building with only thin-air between them and the ground below. Engineers spent several years designing and building the breathtaking swing. By being fixed to the top of a building it reaches new heights – dwarfing other swings around Europe but trailing behind the 1,150ft high mechanical rides at the Stratosphere Hotel in Las Vegas, Nevada. (Photo by Huub Zeeman/SWNS.com)

In this August 28, 1963 file photo, the top of the Washington Monument and part of a U.S. flag are reflected in the sunglasses of Austin Clinton Brown, 9, of Gainesville, Ga., as he poses at the Capitol where he joins others in the March on Washington. (Photo by AFP Photo)

Amanda Ashe of Oakland, left, faces off with a police officer during the second night of demonstrations in Emeryville, California, following the grand jury decision in the shooting of Michael Brown in Ferguson, Missouri, November 25, 2014. (Photo by Elijah Nouvelage/Reuters)

Actors dressed as a “Yeti” attend a promotional event for Travel Channel's “Expedition Unknown: Hunt for the Yeti” in Manhattan, New York City, U.S., October 4, 2016. (Photo by Brendan McDermid/Reuters)

A man holding a tray of belongings wades through a road at an area flooded by the Omoigawa river, caused by typhoon Etau in Oyama, Tochigi prefecture, Japan, in this photo taken by Kyodo September 10, 2015. (Photo by Reuters/Kyodo News)

Heidi Klum (not pictured) was greeted by half-naked models arriving at Myer Melbourne on January 27, 2016 in Melbourne, Australia. The supermodel continued her tour of the country promoting her new season of lingerie for Heidi Klum intimates, a brand which she took over from Elle Macpherson in 2014. (Photo by Robert Cianflone/Getty Images)