The logo of the Organization of the Petroleum Exporting Countries (OPEC) is pictured at its headquarters in Vienna, Austria, August 21, 2015. REUTERS/Heinz-Peter Bader

President Hassan Rouhani of Iran addresses the 71st United Nations General Assembly in Manhattan, New York, U.S. September 22, 2016. REUTERS/Carlo Allegri

An elderly man uses a magnifiying glass to see the description on a pack of medicine at a pharmacy in Dandong, Liaoning province, China, March 30, 2011. REUTERS/Jacky Chen/File Photo

Shelves displaying medicines are seen at a pharmacy in Shanghai, China, November 27, 2015. REUTERS/Aly Song/File Photo

Police organize a line of refugees on a stairway leading up to trains arriving from Denmark at the Hyllie train station outside Malmo, Sweden, November 19, 2015. REUTERS/Johan Nilsson/TT News Agency/File Photo

A man walks on a logo of the Monte Dei Paschi Di Siena bank in Rome, Italy September 24, 2013. REUTERS/Alessandro Bianchi/File Photo

An election commission member damages unused ballots with a wood chopper at a polling station in Saransk, Russia, September 18, 2016. REUTERS/Gleb Stolyarov

Election commission members gather at a polling station in Saransk, Russia, September 19, 2016. REUTERS/Alexander Winning