Singer Katy Perry arrives at the Metropolitan Museum of Art Costume Institute Gala 2015 celebrating the opening of “China: Through the Looking Glass” in Manhattan, New York May 4, 2015. (Photo by Lucas Jackson/Reuters)

A man smokes marijuana during a demonstration in support of the legalization of marijuana in Medellin, May 2, 2015. (Photo by Fredy Builes/Reuters)

A woman is tattooed during the Great British Tattoo Show in Alexandra Palace in north London, Britain May 23, 2015. (Photo by Neil Hall/Reuters)

A contestant poses for a photograph backstage ahead of the Miss Gay Jozi pageant in Johannesburg, May 23, 2015. (Photo by Siphiwe Sibeko/Reuters)

Girls ride on a donkey cart with grass for animals on the outside of Nangarhar province, Afghanistan May 19, 2015. (Photo by Reuters/Parwiz)

Cosplayers dressed as Star Wars characters Chewbacca (R) and Darth Vader talk at a Star Wars Day fan event in Tokyo May 4, 2015. Star Wars fans celebrate May 4 as Star Wars Day, a pun that comes from an iconic quote in the movie, “May the Force be with you”. (Photo by Toru Hanai/Reuters)

A visitor tries a baccarat game at the Global Gaming Expo (G2E) Asia in Macau, China May 19, 2015. (Photo by Bobby Yip/Reuters)

A man pulls a cart with collapsed cardboard boxes past boutiques in the Sinchon district in Seoul, May 5, 2015. (Photo by Thomas Peter/Reuters)