A member of the “Exit Point” amateur rope-jumping group jumps from a 44-metre high (144-feet high) waterpipe bridge in the Siberian Taiga area outside Krasnoyarsk, September 28, 2014. Fans of rope-jumping, a kind of extreme sport involving a jump from a high point using an advanced system of amortization including mountaineering and rope safety equipment, attended the Golden Autumn group's jumping season. (Photo by Ilya Naymushin/Reuters)

Labourers walk near trucks loaded with logs, which are trapped on a muddy road, near an unreserved forest in the village of Igbatoro, southwest Nigeria, August 28, 2014. Wood, a form of biomass, is the sole source of energy for hundreds of millions of Africans who lack access to modern sources of power, and logging, both legal and illegal, remains a lucrative business that has contributed to the rapid shrinking of Africa's rainforests and woodlands. (Photo by Akintunde Akinleye/Reuters)

People wait in line to pay their last respects to the late Fidel Castro in Havana, Cuba, Monday, November 28, 2016. Cuba's government has declared nine days of national mourning following Castro's death on Nov. 25. (Photo by Fernando Medina/AP Photo)

A man dresses as a plague doctor at the Bannockburn Live event on June 28, 2014 in Stirling, Scotland. The 700th anniversary of the historic battle that saw the outnumbered Scots conquer the English led by Edward II in the First War of Scottish Independence. (Photo by Peter Macdiarmid/Getty Images)

Models of the “Altyr” fashion theatre, dressed in Khakas national costumes, get over a wooden fence during a photo session, as a part of the rehearsal for the Tun-Pairam traditional holiday (The Holiday of the First Milk) celebration at a museum preserve outside Kazanovka village near Abakan in the Republic of Khakassia, Russia, May 28, 2016. (Photo by Ilya Naymushin/Reuters)

The second and final qualification motor (QM-2) test for the Space Launch System's booster, June 28, 2016, at Orbital ATK Propulsion Systems test facilities in Promontory, Utah. During the Space Launch System flight the boosters will provide more than 75 percent of the thrust needed to escape the gravitational pull of the Earth, the first step on NASA's Journey to Mars. (Photo by Bill Ingalls/NASA)

A machine works on a Rio 2016 Olympic medal at the Casa da Moeda do Brasil (Brazilian Mint) in Rio de Janeiro, Brazil, June 28, 2016. The Casa da Moeda do Brasil is the Brazilian mint, owned by the Brazilian government and administratively subordinated to the Ministry of Finances. It was established in 1694. (Photo by Sergio Moraes/Reuters)

A woman is having a massage at the Lukacs Bath in Budapest, Hungary June 28, 2016. Hungary's capital owes its popularity as a tourist destination partly to its numerous hot springs and bathing culture which have drawn visitors to the area since Roman times. Bath houses range from large, ornate 19th-century buildings like the Gellert and the Szechenyi to tiny Ottoman Turkish-era hamams, some of them more than 500 years old. (Photo by Bernadett Szabo/Reuters)