In this October 5, 2016 photo a man looks at the work “Not to be Reproduced” by Rene Magritte at the Kunsthalle art gallery in Hamburg, Germany. The exhibition, which runs from Oct. 7, 2016 until Jan. 22, 2017, features more than 150 masterpieces of surrealism from four of the most significant European private collections of the 20th century. (Photo by Daniel Reinhardt/DPA via AP Photo)

A participant poses with his laptop during the 33rd Chaos Communication Congress on its opening day on December 27, 2016 in Hamburg, Germany. The annual event is bringing together 12,000 computer hackers and activists who will meet over the next four days to share expertise and discuss topics related to the society and the digital world. (Photo by Morris MacMatzen/Getty Images)

People dressed as zombies participate in a parade for World Zombie Day 2016 in London's West End, Britain on October 9, 2016. (Photo by Splash News and Pictures)

Singer Katy Perry arrives at the Metropolitan Museum of Art Costume Institute Gala 2015 celebrating the opening of “China: Through the Looking Glass” in Manhattan, New York May 4, 2015. (Photo by Lucas Jackson/Reuters)

A mahout rides an elephant at Tad Sae Waterfall outside Luang Prabang, Laos July 31, 2016. Protected by the United Nations cultural heritage agency UNESCO, Luang Prabang is one of the most alluring places in the region – a city that evokes old-world romance that has gained a reputation as a travellers' Shangri La. (Photo by Jorge Silva/Reuters)

In this handout photo provided by Warner Brothers Pictures and Village Roadshow Pictures, Tom Cruise plays Lieutenant Colonel Bill Cage, a soldier who replays his last day while trying to fight aliens, in director Doug Liman's “All You Need Is Kill”. The film is set to premiere on March 14, 2014. (Photo by David James/Warner Brothers Pictures)

Heidi Klum direct a photoshoot for “Germany's Next Top Model” on set filming on Hollywood Boulevard, Los Angeles, USA on January 25, 2017. (Photo by Splash News and Picture)

Lara Stone at Mark's Club on October 27, 2016 in London, England. (Photo by Mark Milan/GC Images)