A fighter of Libyan forces allied with the U.N.-backed government fires a shell with Soviet made T-55 tank at Islamic State fighters in Sirte, Libya, August 2, 2016. (Photo by Goran Tomasevic/Reuters)

An Egyptian university student drives a hybrid racing car he built with his team to compete at the Global Hybrid-Electric Challenge in Cairo, Egypt September 2, 2016. (Photo by Mohamed Abd El Ghany/Reuters)

Jason Bregartner and his son Jason Jr., 2, sit in costume with J.D. Mirable at a bustop during the NYC Zombie Crawl in New York, October 18, 2015. (Photo by Shannon Stapleton/Reuters)

A man smiles as he carries firewood he bought on a street amid ongoing fuel and cooking gas shortages in Yemen's capital Sanaa December 2, 2015. (Photo by Khaled Abdullah/Reuters)

German KUKA Robotics' robot LBR iiwa demonstrates a flower arrangement at the International Robot exhibition in Tokyo, Wednesday, December 2, 2015. (Photo by Shizuo Kambayashi/AP Photo)

Attendees engage in cosplay and wearing costumes during WonderCon 2016 Day 2 at Los Angeles Convention Center on March 25, 2016 in Los Angeles, California. (Photo by Frazer Harrison/Getty Images)

Race goers are pictured during the Investec Ladies Day at Epsom Downs Racecourse on June 2, 2017 in Epsom, England. (Photo by News Group Newspapers Ltd)

Martin Lacey Jr. with a lion during the premiere of the Circus Krone program “Circus der Preistraeger” at Circus Krone on February 2, 2016 in Munich, Germany. (Photo by Hannes Magerstaedt/Getty Images)