In this March 12, 2015 photo, a man tours a graffiti exhibition at the Museum of Modern Art, in Bogota, Colombia. The city-run museum recently held an exhibition highlighting the work of Bogota street artists who go by aliases such as Joems and the MonsTruacioN collective. (Photo by Fernando Vergara/AP Photo)

This picture taken on March 21, 2015 shows a couple kissing in front of blooming cherry blossoms in Wuhan in central China's Hubei province. The cherry blossoms, now in full bloom, attracted tens of thousands of visitors, local media reported. (Photo by AFP Photo/Stringer)

A supporter welcomes US army convoy as it enters Czech Republic in Harrachov, Sunday, March 29, 2015. The “Dragoon Ride” convoy started last week from Estonia and passed through Latvia, Lithuania and Poland before entering the Czech Republic on a return journey to a German base. (Photo by Petr David Josek/AP Photo)

Yenny Mamani "Marta la Altena", top, grabs Leonor Cordova "Angela la Simpatica" in a hold during a Bolivian wrestling Cholitas fight in Madrid, Spain, Thursday October 8, 2015. (Photo by Paul White/AP Photo)

North Korean soldiers participate in a mass military parade at Kim Il-Sung square in Pyongyang on October 10, 2015. North Korea was marking the 70th anniversary of its ruling Workers' Party. (Photo by Ed Jones/AFP Photo)

North Korean military participate in the celebration of the 70th anniversary of the founding of the ruling Workers' Party of Korea, in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang on early October 11, 2015. (Photo by Reuters/KCNA)

People play "Palin", a traditional ritual and ancestral Mapuche game played with curved sticks called "Chuecas" and a wooden ball, during a meet on Dia de la Raza (Day of the Races), also known as Columbus Day in Vina del Mar, Chile October 11, 2015. (Photo by Rodrigo Garrido/Reuters)

The aurora borealis, or the northern lights occur over Derwentwater, near Keswick, England, Thursday October 8, 2015. The northern lights are the result of collisions between gaseous particles in the Earth's atmosphere with charged particles released from the sun. (Photo by Owen Humphreys/PA Wire via AP Photo)