A view of Worker and Kolkhoz Woman, a sculpture by Vera Mukhina, at the main entrance to Moscow's VDNKh exhibition center in Moscow, Russia on September 27, 2017. (Photo by Dmitry Serebryakov/TASS/Barcroft Images)

An American soldier walks ahead of an MKIV (Mark IV) British-made tank, circa 1918. (Photo by Hulton Archive/Getty Images)

In this November 26, 2018 photo, men run during 100 meters athletics competition of the second edition of the Panamanian indigenous games in Piriati, Panama. These games were held in the Embera town of Piriati, some 55 miles (90 kilometers) east of Panama City. (Photo by Arnulfo Franco/AP Photo)

People on inflatable boats enjoy the weather on the Lake Lucerne in Sisikon, Switzerland, August 5, 2018. (Photo by Denis Balibouse/Reuters)

Poshia, 16, who said she is a fashion designer smiles as she holds an umbrella for her relative near princess town, Ghana on November 23, 2018. (Photo by Zohra Bensemra/Reuters)

A child plays with a soap bubble on the city hall plaza on March 14, 2015 in Paris. (Photo by Dominique Faget/AFP Photo)

Alexo Carmona, 2, looks at Coco, a two-year-old pony, in downtown Havana, in this March 6, 2015 file photo. Nearly a quarter of a million people follow the Reuters Instagram account – and it's still growing fast. To mark the mid-point of 2015, Reuters has compiled the twenty most-liked pictures so far. This picture was 20th most popular. (Photo by Alexandre Meneghini/Reuters)

Michal Navratil of the Czech Republic performs after the men's 27 meter high dive final at the Swimming World Championships in Kazan, Russia, Wednesday, August 5, 2015. (Photo by Denis Tyrin/AP Photo)