Participants wearing masks during a hazy day at the Beijing International Marathon in front of Tiananmen Square, in Beijing, October 19, 2014. (Photo by Reuters/Stringer)

Two Bulgarian tourists pose in front of the Eiffel Tower in Paris on their last day in the capital on March 24, 2014. (Photo by Franck Fife/AFP Photo)

A migrant labourer brushes his teeth in front of a scrapped helicopter model in Mumbai, India, April 13, 2016. (Photo by Danish Siddiqui/Reuters)

A model poses in front of phone boxes for a photographer in London, United Kingdom on Friday, October 1, 2021. (Photo by Frank Augstein/AP Photo)

Protesters wear gas masks in the front of the Romanian Environment Ministry in Bucharest March 4, 2019, to demand better air. Dozens of people holding placards reading “Our children don't breath air anymore” gather in the front of the Environment Ministry to ask for better breathable air in Bucharest. (Photo by Daniel Mihailescu/AFP Photo)

A Mexican wearing a period costume re-enacts the battle of Puebla, in the Penon de los Banos neighbourhood of Mexico City, Mexico May 5, 2016. The battle marked the defeat of French forces by Mexican troops and local Indians in the central state of Puebla in 1862. During the re-enactment, participants fired homemade shotguns loaded with gunpowder and hundreds of men dressed as Indian peasants fought mock battles against others dressed as French invaders. (Photo by Henry Romero/Reuters)