A model presents a creation by Maltese hairstylist Marielle Calleja of Prive at the Malta Fashion Awards 2015 at the Marsa Shipbuilding warehouse in Marsa, outside Valletta in Malta, May 16, 2015. (Photo by Darrin Zammit Lupi/Reuters)

Jason Garcia poses as The Joker from Batman at the 2015 Comic-Con International in San Diego, California, July 9, 2015. (Photo by Sandy Huffaker/Reuters)

A model presents a creation during the 2015 Victoria's Secret Fashion Show in New York, November 10, 2015. (Photo by Lucas Jackson/Reuters)

A model presents a creation during the 2015 Victoria's Secret Fashion Show in New York, November 10, 2015. (Photo by Lucas Jackson/Reuters)

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)

An Iraqi woman attends a festival commemorating the International Day of Peace in Baghdad, September 21, 2015. (Photo by Thaier al-Sudani/Reuters)

A person dressed as a pumpkin monster poses at the premiere of the film “Goosebumps”, in Los Angeles, California October 4, 2015. (Photo by Danny Moloshok/Reuters)

A girl pulls her sister in a discarded basket in the Rashidabad neighborhood of Peshawar, Pakistan October 18, 2015. (Photo by Khuram Parvez/Reuters)