A reveller is photographed during a traditional Maracatu carnival in Olinda, Brazil February 8, 2016. (Photo by Ueslei Marcelino/Reuters)

Disguised revellers parade on the occasion of the Cortege during the Carnival in Basel, Switzerland, February 17, 2016. (Photo by Georgios Kefalas/EPA)

Dogs perform during “Stars and starlets”, a new programme, at the National Circus in the Ukrainian capital of Kiev April 30, 2015. (Photo by Gleb Garanich/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)

Sumo wrestlers compete during the “Honozumo” ceremonial sumo tournament at the Yasukuni Shrine in Tokyo April 3, 2015. (Photo by Thomas Peter/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)

Competitors release their hens during the World Championship Hen Racing Championships in Bonsall, Britain August 1, 2015. (Photo by Darren Staples/Reuters)

Iraqi forces gather during an operation to attack Islamic State militants in Mosul, Iraq, October 21, 2016. (Photo by Reuters/Stringer)