The “EMIEW3” robot (R) demonstrates communicating with a visitor during a press preview in Tokyo on April 8, 2016. Japanese electronics giant Hitachi unveiled its humanoid customer service and guidance robot “EMIEW3” and “remote brain” robotics IT platform. (Photo by Toshifumi Kitamura/AFP Photo)

Olaf Niess catches swans on the river Alster near the town hall in Hamburg, Germany, 17 November 2015. The Alster swans are moving to their ice-free winter quarters on the Eppendorf Muehlenteich millpond until spring. (Photo by Bodo Marks/EPA)

Pakistani female police commandos attend a training session in Nowshera, near Peshawar Pakistan, Wednesday, February 11, 2015. Authorities formed a Special Combat Unit after Taliban militants stormed a Peshawar school on Dec. 16, 2014 and massacred 150 children and teachers. (Photo by Mohammad Sajjad/AP Photo)

A model of a ghost made from translucent fibreglass is lit from inside at Gem's (Wax Models) Ltd, in the Portobello Road area of west London. The ghost is due to go to the Capistrano Mission Museum in California, where tourists are told the legend of how he frightened a young Indian girl novice to death. 1st May 1965. (Photo by Chris Ware/Keystone Features)

Taking it all in at Trolltunga, a piece of rock which juts horizontally out of a mountain, 700 metres above lake Ringedalsvatnet in Norway. (Photo by Sam Rogers/GuardianWitness)

An Israeli policeman prevents a Palestinian man from entering the compound which houses al-Aqsa mosque, known by Muslims as the Noble Sanctuary and by Jews as the Temple Mount, in Jerusalem's Old City September 28, 2015. (Photo by Ammar Awad/Reuters)

Father Christmas arriving at the Arding and Hobbs store in Clapham Junction, London, 2nd November 1926. (Photo by H. F. Davis/Topical Press Agency/Getty Images)

A painting of Chinese President Xi Jinping holding an umbrella is seen on the toilet wall in a guesthouse in Hong Kong December 30, 2014. Set up in a small apartment in the Causeway Bay shopping district, the guesthouse that gives what it calls “Umbrella Revolution Occupation Experience” charges guest HK$100 (US$13) a night to stay in a tent surrounded by pro-democracy banners, a cardboard cutout of President Xi Jinping holding a yellow umbrella, and serve toilet paper printed with the face of embattled leader of Hong Kong chief executive Leung Chun-ying. (Photo by Tyrone Siu/Reuters)