Katy Perry attends the European premiere of Katy Perry: «Part Of Me 3D» at Empire Leicester Square on July 3, 2012 in London, England. (Photo by Mike Marsland)

Indonesian residents look at the Mount Sinabung volcano as it spews volcanic ash near the Tiga Pancur village in Karo, North Sumatra on August 3, 2016. Volcanic eruptions in Indonesia in recent days have forced the closure of two airports and disrupted some flights to the holiday island of Bali, officials said August 3. Mount Sinabung, a volcano on the western island of Sumatra which has been rumbling for some time, also erupted violently on August 2, although its ash clouds did not disrupt any flights. (Photo by Y.T. Haryono/AFP Photo)

One of three young oriental small-clawed otters eats a meatball on June 18, 2015 in a zoo in Dresden, eastern Germany. The oriental small-clawed otter female Fussi gave birth to 3 healthy pups. Its pups now leave their burrow to explore the environment. (Photo by Arno Burgi/AFP Photo/DPA)

Julian, left, is photographed by his mother with friend Gianluca, right, under water at a public pool in Gelsenkirchen, Germany, on a hot Friday, July 3, 2015. Germany faces a heat wave with temperatures up to 38 degrees Celsius (100 degrees Fahrenheit) at the weekend. (Photo by Martin Meissner/AP Photo)

Migrants react after boarding the Migrant Offshore Aid Station (MOAS) ship MV Phoenix some 20 miles (32 kilometres) off the coast of Libya, August 3, 2015. Some 118 migrants were rescued from a rubber dinghy off Libya on Monday morning. The Phoenix, manned by personnel from international non-governmental organisations Medecins san Frontiere (MSF) and MOAS, is the first privately funded vessel to operate in the Mediterranean. (Photo by Darrin Zammit Lupi/Reuters)

Base jumpers leap from the 300-metre high skydeck of Malaysia's landmark Kuala Lumpur Tower against the backdrop of the city's skyline on October 3, 2016 during the annual International KL Tower Base-Jump event. (Photo by Manan Vatsyayana/AFP Photo)

Passengers from a passing train watch as rescue workers search a train which crashed in Karachi, Pakistan, November 3, 2016. At least 17 people have been killed and dozens more injured after two trains carrying hundreds of passengers collided in Pakistan's southern port city of Karachi, officials said. (Photo by Akhtar Soomro/Reuters)