People on motor bikes celebrate American President Barack Obama's visit to Kenya by holding up a photo, center top, of the president and First Lady Michelle Obama in Kisumu, Kenya, Saturday, July 25, 2015. President Barack Obama heralded Africa as a continent “on the move” Saturday as he opened a U.S.-sponsored business summit in Kenya, the East African nation where he has deep family ties. (Photo by AP Photo)

Members of the Michiana Rocketry prep a 10-foot, 450 pound porta-potty, mounted on rocket motors for launching, Saturday, December 6, 2014, from a field in Three Oaks, Mich. It made an arc and almost landed on a spectator’s pickup truck, 2,000 feet away. A group of Michiana Rocketry club members planned the project for more than two years. The club is trying to increase awareness of rocketry as a hobby and prove it’s possible to turn a porta-potty into a rocket and launch it successfully. About 30 people worked on the rocket, from engineers to sales people who lined up sponsors. (Photo by Don Campbell/AP Photo/The Herald-Palladium)

A motorized three-wheeled taxi carrying Muslim students drives past the Starbucks cafe where Thursday's attack occurred in Jakarta, Indonesia, on Friday, January 15, 2016. A day after attackers detonated bombs and engaged in gunbattles with police in the central part of Indonesia's capital, Jakarta tried to get itself back on track. (Photo by Dita Alangkara/AP Photo)

A student protester throws a stone against a riot police vehicle during a demonstration to demand changes in the education system in Santiago, Chile, April 21, 2016. (Photo by Ivan Alvarado/Reuters)

Performers are reflected in a displayed vehicle before going onto the stage during the Auto China 2016 auto show in Beijing, China, April 29, 2016. (Photo by Damir Sagolj/Reuters)

A demonstrator kicks a riot police vehicle during an unauthorized march called by the Chilean student federations to protest against government's education reform, in Santiago, Chile July 5, 2016. (Photo by Ivan Alvarado/Reuters)

A traffic police officer directs vehicles at a street junction during sunset in Pyongyang, North Korea, Thursday, August 25, 2016. (Photo by Dita Alangkara/AP Photo)

Labourers load a three-wheeled vehicle onto the back of a van at the Mercato market in Addis Ababa October 9, 2015. Addis Ababa's “Mercato” – Italian for “market” – is reputedly the biggest open-air market in Africa, lying in the west of the capital. (Photo by Tiksa Negeri/Reuters)