Passengers check their mobile devices as a bin is full of garbage during a protest by the cleaning staff at Barcelona's airport, Spain, December 1, 2016. (Photo by Albert Gea/Reuters)

Traffic police stand at the side of a road in Pyongyang on November 25, 2016. (Photo by Ed Jones/AFP Photo)

A farmer rides a truck in a village near Nong Khai, Thailand, September 16, 2015. (Photo by Jorge Silva/Reuters)

A Pakistani monkey handler Naseer Khan plays flute to attract passers by for a monkey show to earn his living in Islamabad, Pakistan, Monday, September 7, 2015. (Photo by B. K. Bangash/AP Photo)

An Egyptian passenger sits on the locomotive of a train as it leaves Cairo train station in Egypt, Wednesday, October 14, 2015. (Photo by Amr Nabil/AP Photo)

A man steers with his legs while riding a motorcycle on a road in Vietnam's northern Hoa Binh province, outside Hanoi, October 15, 2015. (Photo by Reuters/Kham)

People clash with Venezuelan National Guards as they try to cross the border to Colombia over the Francisco de Paula Santander international bridge in Urena, Venezuela December 18, 2016. (Photo by Carlos Eduardo Ramirez/Reuters)

Ethnic Wa performer dressed as United Wa State Army (UWSA) soldiers perform a traditional dance in Mongmao, Wa territory in northeast Myanmar October 1, 2016. Wa State is an unrecognised state in Myanmar (Burma) and is currently subsumed under the official Wa Special Region 2 of northern Shan State. The Wa were once known as the “Wild Wa” by the British due to their practice of headhunting. (Photo by Soe Zeya Tun/Reuters)