Cars slowly move along a bridge in traffic jam in central Moscow, Russia on December 11, 2018. (Photo by Yuri Kadobnov/AFP Photo)

Students at the Cuba's National Ballet School (ENB) watch a class from outside the classroom in Havana, Cuba, October 12, 2016. Catherine Conley, the first American full-time student at Cuba's prestigious National Ballet School, hopes to gain an edge back home by learning the powerful Cuban style with its dazzling turns and jumps. (Photo by Alexandre Meneghini/Reuters)

A student from the General Yermolov Cadet School takes part in weapons training during a two-day field exercise near the village of Sengileyevskoye, just outside the south Russian city of Stavropol April 13, 2014. The General Yermolov Cadet School in the southern Russian city of Stavropol is a state-run institution that teaches military and patriotic classes in addition to a normal syllabus. (Photo by Eduard Korniyenko/Reuters)

Girls enjoy nice weather at a park in front of the Pothonggang Department Store in central Pyongyang October 11, 2015. (Photo by Damir Sagolj/Reuters)

A jogger runs on the bank of Donaukanal channel in central Vienna, Austria, September 5, 2016. (Photo by Heinz-Peter Bader/Reuters)

A subway worker walks away after a train departed the station in central Pyongyang, North Korea May 7, 2016. (Photo by Damir Sagolj/Reuters)

Wearing a satin and lastex top and a skirt made of fishnet Ann Evors, a Paramount player, poses for the cameramen on the beach, circa 1928. (Photo by Central Press)

A woman participates in the “Carnaval na Central” block party in Rio. (Photo by Felipe Dana/Associated Press)