This May 11, 2016 photo shows the backside of a bus decorated with a provocative mural, in Acapulco, Mexico. (Photo by Enric Marti/AP Photo)

In this photo taken on Saturday, April 22, 2017, a drawing “King for a day” is made on the back of a muddy truck by artist Nikita Golubev in Moscow, Russia. The grimy trucks traversing the polluted and dusty streets of Moscow have inspired Golubev to use white vans and trucks as his canvas to create this ephemeral street art and signs his drawings Pro Boy Nick. (Photo by Pavel Golovkin/AP Photo)

A work by Chinese artist ROBBBB is seen on a wall in the ruins of a building in Beijing September 27, 2015. The 25-year-old artist in Beijing prefers to display his work on the walls of abandoned buildings, rather than a gallery. His artwork is mostly derived from photos of people he sees in the Chinese capital, anyone ranging from elderly people to construction workers. (Photo by Jason Lee/Reuters)

Picture shows a mural painting in Ferrol, on September 2, 2018, during the annual street art festival “Meninas de Canido” set up in 2008 to breathe new life in a dying neighborhood. Angry at the announced death of his neighborhood, Canido, in Ferrol, Eduardo Hermida painted his version of Velazquez's “Meninas” on a wall. An act of protest that gave birth to a festival and gave new colors to this city of Galicia. (Photo by Miguel Riopa/AFP Photo)

French street artist OakOak produces creative works of art that use the characteristics of a location such as a light post, road sign and even a crack in the wall as inspiration but also as key elements in the work. (Photo by OakOak)

The giant mural titled “Under the Hand” by Maclaim Crew is visible on a building facade in Kreuzberg district on June 26, 2014 in Berlin, Germany. Berlin, with its long tradition of counter-culture, has become a mecca for street art of all dimensions and messages. (Photo by Sean Gallup/Getty Images)

In this Monday, July 24, 2017 photo, a police officer walks in front of a mural during a protest demanding an end to the current pension fund system, in Santiago, Chile. Protesters say the government pension system robs retirees of fair pension payments, and are demanding a new social security system with higher payments. (Photo by Esteban Felix/AP Photo)