Brazilian graffiti artist Eduardo Kobra (C) puts the final touches to his piece of art in tribute to Brazilian architect Oscar Niemeyer, next to his assistants, at the financial center on Sao Paulo's Avenida Paulista January 22, 2013. Kobra created the 56-metre (61-yard) tall graffiti artwork as a tribute to Niemeyer, one of the 20th century's most influential modernist architects. Niemeyer died in December 2012, aged 104. (Photo by Andre Penner/AP Photo)

A woman poses for a photograph in front of a 3D painting at HK 3D Museum in Hong Kong June 26, 2014. (Photo by Tyrone Siu/Reuters)

HRP-4C, a five-foot humanoid robot developed at Japan's National Institute of Advanced Industrial Science and Technology, sings and dances with performers at the Digital Contents Expo in Tokyo on October 17, 2010. The robot runs entertainment software called Choreonoid, a name formed from the words “choreograph” and “humanoid”. (Yoshikazu Tsuno/AFP)

Grumpy Cat in Las Vegas, America on August 5, 2014. Grumpy Cat aka Tardar Sauce has died on May 14, 2019 at home in Arizona at the age of seven due to complications from a urinary tract infection. Her family's statement said: “Besides being our baby and a cherished member of the family, Grumpy Cat has helped millions of people smile all around the world – even when times were tough. Her spirit will continue to live on through her fans everywhere. Grumpy's Family – Tabatha, Bryan and Chyrstal”. (Photo by Mediapunch/Shutterstock)

A visitor poses for a photograph in front of a 3D painting depicting a Japanese Imperial army soldier at a 3D art gallery in Beijing January 16, 2015. (Photo by Kim Kyung-Hoon/Reuters)

Undated handout photo issued by World Architecture Festival 2013 of The Halley VI centre designed by British architects Hugh Broughton in Antarctica which is a dismantlable research station created in the icy wastes for the British Antarctic Survey and has been shortlisted for a global architecture award. (Photo by World Architecture Festival 2013/PA Wire)

At the Krasnopresnenskaya station, the benches come from the Cathedral of Christ-Sauveur, which was built from 1839 to 1883 in memory of the victory of Russia against the army of Napoleon I. The cathedral was destroyed under Stalin in 1931, but the benches remained intact. Metro architects decided to install them in some stations. (Photo by Didier Bizet/The Washington Post)