A boy dressed as the Star Wars character Darth Vader attends a Star Wars themed church service, at the Zion Church in Berlin, Sunday, December 20, 2015. About 500 people, some carrying light saber props or wearing Darth Vader masks, attended the service, more than twice as many as usual on a Sunday. (Photo by Markus Schreiber/AP Photo)

Turkish artist Nezaket Ekici performs a live art performance entitled 'Emotion in Motion' on the first day of Art Basel 2015, Hong Kong, China, 13 March 2015. The Hong Kong show of Art Basel features 233 galleries from 37 countries and territories, presenting works ranging from the Modern period of the early 20th century to the most contemporary artists of today, according to the official press release. (Photo by Alex Hofford/EPA)

A couple who did not give their names walk in downtown Havana, February 2, 2015. (Photo by Alexandre Meneghini/Reuters)

Emilio Gonzalez from Venezuela poses during the Cali Tattoo Festival in Cali, Colombia, September 12, 2015. (Photo by Jaime Saldarriaga/Reuters)

People are reflected in a shop window as they walk along a street in a shopping district in Tokyo, Japan June 25, 2015. (Photo by Thomas Peter/Reuters)

A migrant boy sits on railway tracks at a train station in Tovarnik, Croatia, September 20, 2015. (Photo by Antonio Bronic/Reuters)

Competitors warm up backstage during the Arnold Classic Europe bodybuilding event in Madrid, Spain, September 25, 2015. (Photo by Susana Vera/Reuters)

A dog catches a wave during the Surf City Surf Dog Contest in Huntington Beach, California September 27, 2015. (Photo by Lucy Nicholson/Reuters)