A boy covers his head with fallen leaves as he enjoys a stroll with his family in a park in downtown Frankfurt, Germany, November 6, 2016. (Photo by Kai Pfaffenbach/Reuters)

A couple photograph The Helmsley Building on Park Avenue, lit in honor of the victims of the Nice attacks, in Manhattan, New York, U.S., July 15, 2016. (Photo by Brendan McDermid/Reuters)

Partially demolished houses stand in the Vila Autodromo slum with the Rio 2016 Olympic Park in the background in Rio de Janeiro, Brazil, February 25, 2016. (Photo by Ricardo Moraes/Reuters)

Women jump as they pose for photo in front Patuxay park, ahead of the ASEAN Summit in Vientiane, Laos September 5, 2016. (Photo by Soe Zeya Tun/Reuters)

The 18th Annual Buda County Fair and Weiner Dog Races was held at city park in Buda Sunday April 26, 2015 sponsored by the Lions Club. (Photo by Ralph Barrera/Austin American-Statesman)

Artist Joe Hill poses on his 3D artwork, from the “Joe and Max” project as part of an advertising campaign, during its presentation at a park in Moscow, Russia, July 4, 2015. (Photo by Sergei Karpukhin/Reuters)

Emma the Maltese's fur blows in the wind as she rides in her owner's purse on 5th Avenue at Central Park in New York December 2, 2014. (Photo by Carlo Allegri/Reuters)

People watch as an acrobat rides his motorcycle around a circular track at an entertainment park set up outside a shrine in Rawalpindi, Pakistan, on June 19, 2013. (Photo by Muhammed Muheisen/Associated Press)