A lady smiles during the annual Calabar cultural festival in Calabar, Nigeria, December 28, 2015. Picture taken December 28, 2015. (Photo by Reuters/Stringer)

An aircraft passes over houses at it lands at Heathrow Airport near London, Britain, December 11, 2015. Picture taken December 11, 2015. (Photo by Neil Hall/Reuters)

Star Wars fan Mike Deguzman practices with a toy lightsaber after purchasing some new toys that went on sale at midnight in advance of the film “Star Wars: The Force Awakens” in Times Square in the Manhattan borough of New York, September 4, 2015. (Photo by Carlo Allegri/Reuters)

A man rows a boat on the Dal Lake as a woman holds an umbrella during snowfall in Srinagar February 19, 2015. (Photo by Danish Ismail/Reuters)

Young gymnasts practice pull-up on a bar at a gymnasium of a sports school in Jiaxing, Zhejiang province April 11, 2015. (Photo by William Hong/Reuters)

A woman takes part in an extreme run competition in Zhodino, east of Minsk, September 26, 2015. (Photo by Vasily Fedosenko/Reuters)

A girl and boy carry a basket of fish in Kyaukpyu township, Rakhine state, Myanmar October 6, 2015. (Photo by Soe Zeya Tun/Reuters)

Dancers perform on stage during Diwali celebrations in Leicester, Britain November 11, 2015. (Photo by Darren Staples/Reuters)