Furniture design “Chair” by Allen Jones ( £600,000-800,000) is seen at Christie's London on September 29, 2017 in London, England. Christie's Auction House is to sell millions of pounds worth of art and design from the 20th and 21st centuries during Frieze Week from October 3rd to October 7th. (Photo by Nils Jorgensen/Rex Features/Shutterstock)

In this September 27, 2017 file photo, girls walk past a wall riddled with bullet holes from shootings between rival drug traffickers, at the Rocinha slum, in Rio de Janeiro, Brazil. Violence is on the rise in Rio's slums after several years of decline, and the killings of kids have shocked even residents long inured to deaths from gangs and police. (Photo by Silvia Izquierdo/AP Photo)

A female sniper of the Syrian Democratic Forces (SDF) monitors the area during a celebration at the iconic Al- Naim square in Raqa on October 19, 2017, after retaking the city from Islamic State (IS) group fighters. The SDF fighters flushed jihadist holdouts from Raqa' s main hospital and municipal stadium, wrapping up a more than four- month offensive against what used to be the inner sanctum of IS' s self- proclaimed “caliphate”. (Photo by Bulent Kilic/AFP Photo)

A student from the union territory of Pondicherry prepares to take part in the inaugural session of the national Balrang Festival 2017 in Bhopal, India, 20 December 2017. More than 500 participants from 26 states across the country take part in the three-day long cultural event to showcase their performances. The festival organised by Madhya Pradesh School Education Department and Indira Gandhi Rashtriya Manav Sangralaya. (Photo by Sanjeev Gupta/EPA/EFE)

A confiscated female orangutan smuggled from Indonesia looks out from a cage before being sent back home to Indonesia, at Khao Pratupchang Wildlife Breeding Center in Ratchaburi province, Thailand, 11 November 2015. According to media reports, Thailand will return fourteen smuggled orangutans to Indonesia on 12 November, after Thai authorities found them in 2010 by a roadside in Phuket province, apparently on their way to a private zoo. (Photo by Narong Sangnak/EPA)

Artist Heather Dewey-Hagborg's 'Stranger Visions', comprising of 3D printed faces extracted from DNA taken from discarded cigarette butts and chewing gum, is displayed at the Big Bang Data exhibition at Somerset House on December 2, 2015 in London, England. The show highlights the data explosion that's radically transforming our lives. It opens on December 3, 2015 and runs until February 28, 2016 at Somerset House. (Photo by Peter Macdiarmid/Getty Images for Somerset House)

Russian Mi-28N from the Berkuty (Golden Eagles) helicopter display team fly in formation during the “Aviadarts” military aviation competition at the Dubrovichi range near Ryazan, Russia, August 2, 2015. The aircraft started dipping down due to back propeller failure and crashed, killing one of two pilots, according to a Reuters photographer and official representatives of the competition. The aviation contest is part of the International Army Games, which are held in Russia from the 1st till the 15th of August with participants from 17 countries, according to organizers. (Photo by Maxim Shemetov/Reuters)

A picture made available on 09 September 2015 shows traditional mud men dancers from the Asaro District of Goroka in the Eastern Highlands Province of Papua New Guinea perform for the official opening of the Pacific Islands Forum in Port Moresby, Papua New Guinea, 08 September 2015. The Pacific Islands Forum goes from 07 to 11 September and discusses the regions vulnerability to Climate Change. (Photo by Mick Tsikas/EPA)