Riot police stand guard behind a fire as refinery workers hold a blockade of the oil depot of Douchy-Les-Mines to protest against the government's proposed labour reforms, on May 25, 2016. Refinery workers stepped up strikes that threaten to paralyse France weeks ahead of the Euro 2016 tournament as the government moved to break their blockades, escalating a three-month tug-of-war over labour reforms. (Photo by François L.O./AFP Photo)

Boeing 747-400 of KLM in approach for the “Princess Juliana” airport, Netherlands Antilles Sint Maarten on July 2, 2002. (Photo by LUPOO/Ullstein Bild via Getty Images)

The new Toyota Concept-i concept car, designed to learn about its driver is unveiled during the Toyota press conference at CES in Las Vegas, January 4, 2017. (Photo by Rick Wilking/Reuters)

A reindeer is seen as people visit ice sculptures illuminated by coloured lights at the Harbin Ice and Snow Festival to celebrate the new year in Harbin on January 4, 2017. (Photo by Nicolas Asfouri/AFP Photo)

Revelers dance and shout as they listen to music, in front of the main stage, during the 21st Woodstock Festival in Kostrzyn-upon-Odra, Poland July 31, 2015. An estimated 200,000 people attended the ongoing festival, a brainchild of Polish journalist and social campaigner Jerzy Owsiak, on Friday. Owsiak initiated the event to say thank you to those who donated money to his GOCC charity organisation that delivers medical care for children. (Photo by Kacper Pempel/Reuters)

In this September 1, 2015 photo, street artists Jenaro de Rosenzweig, left, and Alejandro Revilla pose for a portrait behind a restaurant's window covered with a mural by artist Francisco Munoz, signed with his artist's name below, in the Roma Norte neighborhood of Mexico City. Rosenzweig and Revilla founded the “Street Art Chilango” cooperative in March 2013, which is filling neighborhoods with public art by local street artists. (Photo by Rebecca Blackwell/AP Photo)

Daniel Filip, Tech Lead Manager for Google Maps, carries the Trekker, a 15-camera device, while mapping the Inca citadel of Machu Picchu for Google Street View in Cuzco, Peru, August 11, 2015. (Photo by Pilar Olivares/Reuters)

A worker holds the head of a fox while killing it with electricity for its fur at a fox farm in Nanzhuang village, Shandong province, China, December 11, 2015. There are over 60 households in the village still raising foxes, raccoon dogs and other animals for the fur trade. China is the world's largest fur producer and exporter, according to state media. (Photo by William Hong/Reuters)