In this September 4, 1963, file photo, a police officer carries off a demonstrator holding a Confederate flag after a group of demonstrators protested enrollment of two African-Americans at Ramsay High School in Birmingham, Ala. The Confederate battle flag has been removed from South Carolina's Statehouse grounds, in the wake of the massacre of nine African-Americans, including a state senator, at an historic black church in Charleston in June 2015. (Photo by AP Photo)

A child plays in front of “Etnias”, a large graffiti wall by Brazilian graffiti artist Eduardo Kobra created ahead of the Rio 2016 Olympic Games at Porto Maravilha in Rio de Janeiro, Brazil, 30 July 2016. The Olympics start on 05 August. Eduardo Kobra hopes to set a Guinness World Record for the largest graffiti created by a single artist. (Photo by Lukas Coch/EPA)

In this August 1, 2014 photo provided by the National Park Service are male caribou antlers in the Oolah Valley, likely the result of a grizzly kill as he migrated south for the winter at the Arctic National Park and Preserve in Alaska. The nation's northernmost national park says its new management plan will have to consider the effects of a new industrial road to the mining district of Ambler, the first road that would be constructed within its Maryland-sized boundaries. (Photo by Cadence Cook/AP Photo/National Park Service)

Men selling sheep wait for customers at a local livestock market, ahead of the Eid al-Adha festival, in Lagos, Nigeria September 11, 2016. (Photo by Akintunde Akinleye/Reuters)

A woman with a Japanese style full back body tattoo at the 12th London International Tattoo Convention, which opened today in Tobacco Dock, east London on September 23, 2016. The show features over 400 of the world's finest, most prestigious and elite tattoo artists as well as a showcasing alternative culture in the form of piercing, burlesque and the Miss Pin Up UK competition. Around 20,000 people will attend over the weekend. (Photo by Michael Preston/Alamy Live News)

A Palestinian protester uses a sling shot to throw stones towards Israeli security forces during clashes on the Israeli border Eastern Gaza City, Friday, November 6, 2015. (Photo by Adel Hana/AP Photo)

A man is silhouetted as he stands on a walkway in the sky lobby at the Chancellery, the seat of German Chancellor Angela Merkel (not pictured) in Berlin, May 7, 2014. (Photo by Thomas Peter/Reuters)

People sit at an oversize picnic table in Soho Square in London May 19, 2014. (Photo by Luke MacGregor/Reuters)