Russian communists lay flowers at Soviet leader Joseph Stalin's tomb on Red Square next to the Kremlin wall in Moscow, Russia, December 21, 2015. Russian communists are marking the 136th anniversary of Josef Stalin's birthday. (Photo by Sergei Ilnitsky/EPA)

In this photo taken late Thursday, May 7, 2015, a prison guard, left, and seated inmates cast shadows on a wall while waiting for the beginning of a rock concert by Romanian band Pro Musica, inside the Popa Sapca jail in Timisoara, western Romania. (Photo by Adi Piclisan/AP Photo)

Buildings in Nogales, Mexico (R) are separated by a border fence from Nogales, Arizona, United Sates, October 9, 2016. Building a wall along the U.S.- Mexico border has been a contentious subject in this year's U.S. presidential election. In parts of California and Arizona, a wall already exists. It runs across rocky deserts, flowing sand dunes and miles of agricultural land. (Photo by Mike Blake/Reuters)

Street artist Irony’s mural of a young woman on Jamaica Street in Liverpool, UK on September 22, 2019. The city has recently been transformed with bold murals painted by local artists on walls and buildings. Recognisable faces including those of the Beatles, Jürgen Klopp and Stephen Hawking. (Photo by Peter Byrne/PA Wire Press Association)

French-Swiss street artist Saype poses as he works on his artwork on a floating barge over the Golden Horn in Istanbul, Turkey on October 23, 2020, as part of the “Beyond Walls” project to create a spray-painted “human chain” across the world to encourage humanity and equality. (Photo by Murad Sezer/Reuters)

A dragon mask for the upcoming Lunar New Year hangs on the wall at Lily Hambali's and lion masks and custome maker in Bogor, Indonesia, 02 February 2015. The Chinese Lunar New Year, known here as Imlek, is only three weeks away. The whole city is getting decked out to celebrate the event on 19 February 2015. (Photo by Adi Weda/EPA)

Protest posters are attached to the walls surrounding the “Occupy London” camp outside St. Paul's Cathedral on November 01, 2011 in London, England. The Dean of St. Pauls Cathedral The Very Reverend Graeme Knowles resigned yesterday over the church's handling of the anti-capitalist “Occupy London” demonstration, which continues to occupy the grounds outside the cathedral. (Photo by Dan Kitwood/Getty Images)

Protester Lauren Digioia wears police tape during an Occupy Wall Street protest in Union Square on March 19, 2012 in New York City. Protesters affiliated with the movement are gathering in Union Square today following 73 arrests at a six-month anniversary rally at Zuccotti Park over the weekend. (Photo by Mario Tama/Getty Images)