A biplane taking part in the Vintage Air Rally lands, in Stellenbosch, near Cape Town, South Africa December 16, 2016. (Photo by Mike Hutchings/Reuters)

In this photo taken Tuesday, April 14, 2015, immigrant men armed with machetes make their way onto a Durban, South Africa, street during clashes with police and in search of locals that attacked foreign shop owners in the city center. (Photo by Tebogo Letsie/AP Photo)

Church members pray at the Dolieb Hill Presbyterian Church in the Protection of Civilians (POC) site at the United Nations Mission in South Sudan (UNMISS) compound in Malakal, South Sudan on Saturday, July 9, 2016. (Photo by Jane Hahn/The Washington Post)

Farmers harvest cocoa fruits at a plantation in Gantarang Keke Village, South Sulawesi, Indonesia May 8, 2015. Sulawesi is at the heart of Asia's largest cocoa producing region, and is where some international confectioners are looking to boost output to feed growing demand for chocolate in the region. (Photo by Yusuf Ahmad/Reuters)

Abandoned cars are seen around a cross in the village of Tbeti near Tskhinvali, the capital of the breakaway region of South Ossetia, Georgia, July 4, 2015. President Vladimir Putin signed a treaty with Georgia's rebel South Ossetia region on March 18 that almost completely integrates it with Russia, alarming Georgia and the West a year after Moscow took over Crimea. Russia won a five-day war with Georgia in 2008 over the fate of South Ossetia and another rebel region, Abkhazia. It formally recognizes both regions as independent states and signed a similar treaty with Abkhazia last year. (Photo by Kazbek Basaev/Reuters)

A North Korean soldier kicks a pole along the bank of Yalu River near the North Korean town of Sinuiju, opposite the Chinese border city of Dandong, February 4, 2014. (Photo by Jacky Chen/Reuters)

Schoolchildren play music to entertain and inspire people on their way home from work Tuesday, March 29, 2016 in Pyongyang, North Korea. North Korea has called a 70-day loyalty drive areas of a major congress of the ruling party scheduled for early May and everyone from students to coal miners have been mobilized nationwide to demonstrate their devotion to the leadership. (Photo by Eric Talmadge/AP Photo)

In this Wednesday, April 12, 2017, photo, waitresses wait outside a restaurant in Pyongyang, North Korea. A generational divide is quietly growing in North Korea, often hidden behind relentless propaganda. On the streets there are young women in not-quite mini-skirts and teenage boys with baseball hats cocked sideways, K-pop style. (Photo by Wong Maye-E/AP Photo)