In this October 29, 2013 photo, Daniel smokes marijuana inside his apartment where he uses a hydroponics system to grow his weed in Mexico City. “I'm not a narco, dude. I just like to smoke”, said Daniel, who spoke on condition that his last name not be used because, he said, his home-grow operation is "super-illegal" despite being for personal use only. (Photo by Eduardo Verdugo/AP Photo)

Brain-on-a-chip. Dazzling in green and magenta this image shows the nerve fibres (in green) produced by neural stem cells (in magenta) as they grow on a synthetic gel. Captured by a technique known as confocal microscopy, the image is part of research shedding light on how tinkering with the environment can affect the way in which nerve fibres grow. (Photo by Collin Edington and Iris Lee/Massachusetts Institute of Technology/Wellcome Images)

A visiter is attracted by the chairs covered with solar panels at the factory of Yingli Green Energy Holding Company, also known as Yingli Solar, on June 20, 2011 in Baoding city of Hebei Province, China. According to a report by the International Energy Agency (IEA), China overtook America as the world' s largest energy consumer in 2010. New energy industries are becoming even more important than in the past. (Photo by Feng Li/Getty Images)

Wrestler known as Gio Malkriado (top) fights with a fluorescent tube with wrestler Ciclope during an extreme wrestling fight at a temporary wrestling ring inside a car wash in Tulancingo Hidalgo, Mexico October 8, 2016. When the time comes for the so-called Extreme Star Fight, six wrestlers climb into the ring. Once the fighting begins, anything goes. They bash each other with chairs and long neon lights, causing small explosions and scattering tiny pieces of glass everywhere. (Photo by Carlos Jasso/Reuters)

LOCOG Chair and former Olympian Lord Sebastian Coe holds a prototype design of the new golden Olympic Torch during its unveiling at St Pancras Station on June 8, 2011 in London, England. (Photo by Dan Kitwood/Getty Images)

A giant ham bread, a typical Venezuelan Christmas dish, is seen on a table during an attempt to break the Guinness World Record for the biggest ham bread, in Caracas November 15, 2014. The giant hallaca more than 120 metres long. (Photo by Carlos Garcia Rawlins/Reuters)

A glass is checked at the table for China's top leaders before the start of a reception to celebrate National Day at the Great Hall of the People in Beijing, China September 30, 2016. China celebrates its National Day on October 1. (Photo by Damir Sagolj/Reuters)

A traditional game that earned hollers from the crowd saw a male rider gallop after a young woman, stretching for a kiss. Only a handful of the men managed the risky peck before the young women turned the tables and thundered after the men with whips in hand. (Photo by Amos Chapple/Radio Free Europe/Radio Liberty)