A passenger waits after his train arrived in Nouadhibou, Mauritania’s second largest city and the main export port for the country’s iron ore industry, on June 25, 2014. The mining company’s employees proudly call their firm the lung of their nation's economy and the train that ferries the ore to the coast stretches some two kilometres, making it one of the world's longest. SNIM mines black iron ore in the northern town of Zouerate, a remote desert location which nevertheless attracts people from all over the country looking for work. (Photo by Joe Penney/Reuters)

A Mercedes-Benz 300 SL “Gullwing” Coupe is displayed during an exhibition of vintage and classic cars by Bonhams auction house at the Grand Palais during the Retromobile week in Paris, France, February 8, 2017. (Photo by Benoit Tessier/Reuters)

A rabbit fails to jump over an obstacle during a rabbit track and field competition on the sidelines of a hunting exhibition in Kromeriz, about 60 km east of Prague, on April 1, 2017. Circa 100 rabbits took part in the competition, including disciplines as long jump, high jump and running on a flat track. (Photo by Radek Mica/AFP Photo)

In this Monday, June 5, 2017, file photo, an Indian woman walks as se searches for recyclable materials at a garbage dumping site on the outskirts of Gauhati, Assam state, India. (Photo by Anupam Nath/AP Photo)

A woman takes a dip in a font on the eve of the Orthodox Epiphany in central Moscow, Russia, January 18, 2016. Orthodox believers mark Epiphany on January 19 by immersing themselves in icy waters regardless of the weather. (Photo by Sergei Karpukhin/Reuters)

The manager of Jinhua Partytime Latex Art and Crafts Factory wears a mask of U S. Democratic presidential candidate Bernie Sanders as he poses and gives a thumbs-up as during a presentation of products to reporters at his factory's showroom in Jinhua, Zhejiang Province, China, May 25, 2016. (Photo by Aly Song/Reuters)

F/A-18 fighter jet takes off from the USS Harry S. Truman aircraft carrier in the eastern Mediterranean Sea June 13, 2016. (Photo by Baz Ratner/Reuters)

2016 Rio Olympics, Gymnastics training, Rio Olympic Arena, Rio de Janeiro, Brazil on August 4, 2016. Close up of the feet of Rebecca Downie (GBR) of United Kingdom as she trains on the beam. (Photo by Dylan Martinez/Reuters)