Four-year-old Rashida from Kobani, Syria, part of a new group of more than a thousand immigrants, sleeps as they wait at border line of Macedonia and Greece to enter into Macedonia near Gevgelija railway station August 20, 2015. (Photo by Ognen Teofilovski/Reuters)

Inês Carvalho (C), accompanied by her sister and cousin, is helped by her aunt to dress up at Alfama neighborhood in Lisbon on June 12, 2014. Carvalho, 18, is one of the revelers from the Alfama march and every Saint Anthony's day, Lisbon's protector, she parades with several other typical neighborhoods of the city. (Photo by Patricia De Melo Moreira/AFP Photo)

Cuban-American artist Jorge Rodriguez-Gerada's six-acre sand and soil “facescape” stretches across the JFK Hockey Field on the north side of the Reflecting Pool along the National Mall October 1, 2014 in Washington, DC. Titled “Out of Many, One” and composed of 2,500 tons of sand, 800 tons of top soil and eight miles of string, the piece is the artist's interpreative blending of 30 different men's faces. Rodriguez-Gereda used high-precision global positioning satellites to place 10,000 wood pegs as waypoints for the giant face. The piece will be open to the public beginning October 4 and will eventually be tilled back into the earth. (Photo by Chip Somodevilla/Getty Images)

A street performer jumps in the air inside Central Park as the colors of autumn become more prevalent in New York, October 29, 2015. (Photo by Lucas Jackson/Reuters)

A boy rides on a snow wagon towed by a robot dressed as a Teddy bear, which only moves forward by moving its legs, during the Ice and snow carnival at Taoranting park in Beijing February 9, 2015. (Photo by Kim Kyung-Hoon/Reuters)

In this May 31, 2016 photo, pieces of watermelon litter the trash area of the Coche public market in Caracas, Venezuela. Staples such as corn flour and cooking oil are subsidized, costing pennies at the strongest of two official exchange rates. But fruit and vegetables have become an unaffordable luxury for many Venezuelan families. (Photo by Fernando Llano/AP Photo)

City buildings stand beyond the giant excavated hole left by the Mir mine, a former open pit diamond mine, in Mirny, Russia, on Tuesday, November 12, 2013. OAO Alrosa, the world's largest diamond producer, raised about $1.3 billion in an oversubscribed share sale from investors including Oppenheimer Funds Inc. and Lazard Ltd.'s asset-management unit, First Deputy Prime Minister Igor Shuvalov said. (Photo by Andrey Rudakov/Bloomberg)

Students stand on the roof of a wooden boat as haze blankets the Musi River while they travel to school in Palembang, on Indonesia's Sumatra island, September 10, 2015. Indonesia is investigating 10 firms over worsening forest fires that have created a blanket of smog over Southeast Asia, threatening them with sanctions if they are found responsible, a government minister said on Tuesday. The thick haze from Indonesia's Sumatra and Kalimantan islands has forced the repeated cancellation of flights in the area and pushed air quality to unhealthy levels in neighbouring Singapore and Malaysia. (Photo by Reuters/Beawiharta)