Hot air balloons fly over the sky in Chiang Mai province, northern Thailand, December 6, 2014. The two-day International Balloon festival 2014 featuring balloon pilots from Germany, Spain, Netherlands, Britain, and Czech Republic is held on December 06-07 2014 to celebrate Thai King Bhumibol Adulyadej's 87th birthday and also aimed to promote the tourism industry in Chiang Mai northern city. (Photo by Pongmanat Tasiri/EPA)

A Filipino worker arranges roasted pigs which they sell in suburban Quezon city, Philippines on Tuesday, December 23, 2014. Roasted pig is popular during Filipino celebrations and traditionally served during a Christmas eve dinner called “Noche Buena” in this predominantly Roman Catholic nation. (Photo by Aaron Favila/AP Photo)

A woman looks at a swimmer getting herself warm after the annual Christmas winter swimming competition in the Vltava river in Prague December 26, 2014. (Photo by David W. Cerny/Reuters)

A man dressed in a condom costume walks at Caleta Portales beach, during a summer awareness campaign by the Chilean Corporation for the Prevention of AIDS in Valparaiso city, northwest of Santiago January 9, 2015. (Photo by Rodrigo Garrido/Reuters)

Rescue workers try to pull out a piece of an exploded Grad missile outside an apartment building in Vostochniy district of Mariupol, Eastern Ukraine, Sunday, January 25, 2015. Indiscriminate rocket fire slammed into a market, schools, homes and shops Saturday in Ukraine's southeastern city of Mariupol, killing at least 30 people, authorities said. The Ukrainian president called the blitz a terrorist attack and NATO and the U.S. demanded that Russia stop supporting the rebels. (Photo by Evgeniy Maloletka/AP Photo)

Protesters wear masks, the left in the colors of the Kenyan national flag, as they join others carrying mock coffins and red-painted crosses, symbolizing the blood of the 28 non-Muslims singled out and killed in the recent attack on a bus in Mandera by Somali militant group al-Shabab, outside government offices in downtown Nairobi, Kenya Tuesday, November 25, 2014. (Photo by Ben Curtis/AP Photo)

Honda MotoGP rider Dani Pedrosa (R) of Spain sprays champagne on an attendant next to Yamaha MotoGP rider Valentino Rossi (C) of Italy after winning the Japanese Grand Prix at the Twin Ring Motegi circuit in Motegi, north of Tokyo, Japan, October 11, 2015. Rossi placed second. (Photo by Issei Kato/Reuters)

Labourers unload gravel from a boat docked in Dala township, opposite Yangon city, Myanmar, November 12, 2015. (Photo by Olivia Harris/Reuters)