A silicon rug in the form of Adolph Hitler on display during an exhibition by Israeli artist Boaz Arad, at the Center for Contemporary Art February 22, 2007 in Tel Aviv, Israel. Arad is an Israeli artist who is dealing with the Holocaust in a provocative way. He uses the Holocaust to discuss human evil and contemporary Israel, which he says is torn and crumbling. (Photo by David Silverman/Getty Images)

A nurse consoles herself with a box of chocolates as she reads a paper-back thriller. (Photo by Hulton Archive/Getty Images). Circa 1955

Iraqi army soldiers fire mortars against the Islamic State militants, at Shahrazad village 2 miles (3 kilometers) east of Mosul, Iraq, Monday, November 14, 2016. A suicide bombing in Iraq targeted the Shiite sacred city of Karbala on Monday, killing at least six civilians, the latest attempt by the Islamic State group to distract from the government forces' offensive on the IS-held northern city of Mosul. (Photo by Hussein Malla/AP Photo)

Let the fun begin. Revellers carry their belongings as they arrive at Worthy Farm in Somerset for the Glastonbury Festival, Britain, June 22, 2016. Around 180,000 are expected to attend. (Photo by Ben Birchall/PA Wire)

Revellers react after falling in the mud at Worthy Farm in Somerset during the Glastonbury Festival, Britain, June 26, 2016. (Photo by Stoyan Nenov/Reuters)

A young Chinese girl dressed in Christmas costume, hugs a pedestrian on a street to celebrate Christmas in Nanjing city, east China's Jiangsu province, 23 December 2015. (Photo by Imaginechina/Splash News)

Models and Caroline Scheufele, Artistic Director and Co-President of Chopard (C) pose during a photocall ahead of the Chopard Gold Party during the 68th Cannes Film Festival in Cannes, southern France, May 18, 2015. (Photo by Yves Herman/Reuters)