A boy runs past one of the exhibits during the Dinosaurs exhibition in Belgrade, Serbia, Thursday, August 21, 2014. “Dino Park” has opened at Belgrade's Kalemegdan Fortress. (Photo by Darko Vojinovic/AP Photo)

A visitor walks on a giant chalk artwork called “Wasting Time” at the Chalk Urban Arts Festival in Sydney on October 25, 2014. The picture is the biggest 3-D artwork created in Australia by two artists, Leon Keer from Holland and Jenny McCracken from Australia. (Photo by Peter Parks/AFP Photo)

Spectators cheer as the United Launch Alliance Delta 4-Heavy rocket, with NASA's Orion spacecraft mounted atop, lifts off from the Air Force Station, December 5, 2014, in Cape Canaveral, Fla. (Photo by Smiley N. Pool/AP Photo/Houston Chronicle)

Libyan leader Muammar Gaddafi attends the inauguration ceremony of Jacob Zuma on May 9, 2009 in Pretoria, South Africa. Jacob Gedleyihlekisa Zuma is South Africa's fourth President since the end of apartheid. (Photo by Foto24/Gallo Images/Getty Images)

A dog from the K9 Division of the Sri Lanka Army’s Commando Regiment performs during an event to mark International Children’s Day at a school in Welisara, Colombo, Sri Lanka, 01 October 2016. Sri Lanka marks the Children's Day on 01 October with more emphasis on prevention of child abuse. (Photo by M.A. Pushpa Kumara/EPA)

A couple dance tango for tourists at Caminito, a touristic hotspot of La Boca neighborhood in Buenos Aires, Argentina, October 15, 2016. (Photo by Enrique Marcarian/Reuters)

A driver steers a lorry laden with bags of plastic bottles across a recycling yard at the outskirts of Beijing, China, August 19, 2016. As authorities try to control Beijing's burgeoning population and capitalize on skyrocketing land prices, scrap collectors say they are being pushed out despite playing a vital role in China's unique recycling ecosystem. (Photo by Thomas Peter/Reuters)

Kuwaitis play in front of kites at for Kuwaiti al-Farsi Kites team, Kuwaiti desert, 50 kilometers south of Kuwait City, 06 January 2017 (Issued 07 January 2017). (Photo by Raed Qutena/EPA)