A swimmer reacts after finishing his competition in a pool carved into thick ice covering the Songhua River during the Harbin Ice Swimming Competition in the northern city of Harbin, Heilongjiang province January 5, 2015. The swimming competition was held on the official launch day of the Harbin International Ice and Snow Sculpture Festival. (Photo by Kim Kyung-Hoon/Reuters)

A boy sitting with his family looks up at a traditional Chinelo costumed dancer during a celebration 40 days after the birth of Jesus, in Xochimilco on the outskirts of Mexico City, February 2, 2015. The tradition of the Chinelo dates back to colonial times and the outfits and masks, which are supposed to resemble the faces of the Europeans and always sport an uptilted beard, became more elaborate between the 1800s and 1900s to make fun of the upper social classes. (Photo by Edgard Garrido/Reuters)

Newly-wed couples attend their group wedding ceremony which was held as part of the Harbin International Ice and Snow Festival in the northern city of Harbin, Heilongjiang province January 6, 2016. As many as 15 couples attend this mass wedding ceremony. (Photo by Aly Song/Reuters)

In this Monday, January 18, 2016 photo, Iranian rock climber, Farnaz Esmaeilzadeh, scales a climbing gym in the city of Zanjan, some 330 kilometers (207 miles) west of the capital Tehran, Iran. Esmaeilzadeh, 27, who has been climbing since she was 13, has distinguished herself in international competitions despite the barriers she faces as a female athlete in conservative Iran. (Photo by Ebrahim Noroozi/AP Photo)

Women pose for a picture at Havana city, Cuba, March 17, 2016. Obama arrives in Havana on Sunday for a historic visit that seals a rapprochement he and Cuban President Raul Castro agreed in December 2014 after 18 months of secret negotiations. (Photo by Ivan Alvarado/Reuters)

When it opened in 1955, the Grande Hotel in the Indian Ocean city of Beira was one of the most luxurious in Africa. Photojournalist Fellipe Abreu documents the lives of the 3,500 people who now fill this long-closed hotel to capacity. (Photo by Fellipe Abreu/The Guardian)

Firefighters attempt to put out a fire at an abandoned building with the protection of St. Louis City Police in St. Louis, Missouri August 19, 2015. Police fatally shot a black man they say pointed a gun at them, drawing angry crowds and recalling the racial tensions sparked by the killing of an unarmed African-American teen in nearby Ferguson, Missouri, just over a year ago. (Photo by Lawrence Bryant/Reuters)

Workers adjust rails at the bed of a drained area of a lake used for the production of salt at the Sasyk-Sivash lake near the city of Yevpatoria, Crimea, September 25, 2015. The area has a long tradition of salt production, prepared from salt flats flooded with water from the Black Sea. (Photo by Pavel Rebrov/Reuters)