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 ship builder walks past a section of the Oasis Class 3 cruise ship at the STX Les Chantiers de l'Atlantique shipyard site in Saint-Nazaire, western France, February 17, 2015. The Oasis-class III vessel is scheduled for delivery in mid-2016. (Photo by Stephane Mahe/Reuters)

Iranians flash the victory sign from their car while celebrating on a street in northern Tehran, Iran, Thursday, April 2, 2015, after Iran's nuclear agreement with world powers in Lausanne, Switzerland. The United States, Iran and five other world powers on Thursday announced an understanding outlining limits on Iran's nuclear program so it cannot lead to atomic weapons, directing negotiators toward achieving a comprehensive agreement within three months. (Photo by Ebrahim Noroozi/AP Photo)

A long exposure image of embers flying off burnt out trees following the wind driven wildfire ranging in the mountain area near Rancho Cucamonga late 30 April 2014. Earlier in the day more than 1,500 homes were evacuated as the Etiwanda fire charred around 1,000 acres in San Barnardino National Forest. (Photo by Stuart Palley/EPA)

A Maasai warrior makes the high jump, in which athletes must touch a high line with the top of their heads, at the annual Maasai Olympics in the Sidai Oleng Wildlife Sanctuary near to Mt. Kilimanjaro, in southern Kenya, Saturday, December 13, 2014. Maasai men and women from the Amboseli and Tsavo region compete for medals and prizes in the event which aims for a sports competition of Maasai skills such as running, jumping, and throwing, to replace lion-hunting as the traditional warrior activity. (Photo by Ben Curtis/AP Photo)

A Minion character dressed in a Christmas theme is pictured in Times Square during unseasonably warm weather on Christmas Eve in the Manhattan borough of New York, December 24, 2015. (Photo by Carlo Allegri/Reuters)

A chicken seller carries his chickens on his head in the market in Peshawar, Pakistan, August 20, 2015. (Photo by Khuram Parvez/Reuters)

An empty cell block is pictured within Joint Task Force Guantanamo's Camp VI at the U.S. Naval Base in Guantanamo Bay, Cuba March 22, 2016. (Photo by Lucas Jackson/Reuters)