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)

Indian Air Force soldiers toss their rifles as they perform during the full-dress rehearsal for Indian Air Force Day at the Hindon air force station on the outskirts of New Delhi October 6, 2015. (Photo by Anindito Mukherjee/Reuters)

Half-naked girls against speed driving in Nizhny, Novgorod Region, Russia on September 5, 2016. Russian drivers are getting quite an eyeful in a bid to make them slow down thanks to topless women flashing speed limit signs at an accident blackspot. A trial of the road safety campaign demonstrated that it helped lower the speed of traffic near a pedestrian crossing in Severny village. (Photo by YouTube)

A picture of Moon Ji-sung, a high school student who died in the Sewol ferry disaster, hangs in her room in Ansan April 7, 2015. Her dream was to be a flight attendant. Nearly a year after the Sewol ferry sank on April 16, 2014, with the death of 250 students, some families keep their children’s bedrooms intact to remember and honour their loved ones. More than 300 people, most of them students and teachers from Danwon High School, are dead, or missing and presumed dead, after the Sewol ferry sank on a routine trip from the port of Incheon, near Seoul, to the holiday island of Jeju. (Photo by Kim Hong-Ji/Reuters)

Saint Nicholas poses with students during a traditional parade in central Brussels, Belgium December 3, 2016. (Photo by Yves Herman/Reuters)

Young female Ibex on the fork of Disteis (2,200 m), near the top of the Jof di Montasio (Friuli, Italy). (Photo by Stefano Zocca)

Adrienne Sipe (L) and Brooke Gilliam of Washington D.C. leap off a snow podium they made near the U.S. Capitol in Washington February 13, 2014. A deadly and intensifying winter storm packing heavy snow, sleet and rain pelted a huge swath of the U.S. East Coast on Thursday, grounding flights and shuttering schools and government offices. (Photo by Kevin Lamarque/Reuters)

Lightning illuminates a thundercloud as a storm front hits the North Sea region near Westerhever, northern Germany, on August 11, 2014. (Photo by Daniel Reinhardt/AFP Photo/DPA)