14 week-old twin polar bear cubs play during their first presentation to the media in Hellabrunn zoo on March 19, 2014 in Munich, Germany. The male and female twins were born on December 9, 2013 in the zoo. (Photo by Alexandra Beier/Getty Images)

Wrestling camel “Faytoncu” adorned with colourful ornaments is escorted by his groom as he waits for the Camel Beauty Contest ahead of the annual Selcuk-Efes Camel Wrestling Festival in the Aegean town of Selcuk, near Izmir, Turkey, January 14, 2017. (Photo by Murad Sezer/Reuters)

Miss Langata Prison 2016 Ruth Kamande poses for a photograph as female inmates participate in a fashion parade as part of their Valentine's Day celebration, dubbed “love behind bars” inside the Langata Women Maximum Security Prison in Kenya's capital Nairobi, February 14, 2017. (Photo by Thomas Mukoya/Reuters)

Sri Lankan participants control their bulls during a traditional cart race to mark the Sri Lanka National New Year in Homagama near Colombo on April 23, 2017. The new year marked by both the majority Sinhalese and minority Tamil population fell on April 14. (Photo by Lakruwan Wanniarachchi/AFP Photo)

Afghan paraglider Leeda Ozori, 21, walks after practicing in Kabul, Afghanistan September 14, 2015. She is one of a group of young Afghans taking to the skies of a capital where military helicopters and surveillance balloons are a far more familiar sight. Women in Afghanistan's conservative Muslim society are increasingly entering areas such as education, sports and the workplace, but most still wear the head-to-toe garment, the burqa. (Photo by Mohammad Ismail/Reuters)

A s*x worker (C) stages a performance to denounce what they say is abuse and social stigma against them in Madrid, Spain, October 14, 2015. Placard reads "Prostitutes are the ones that make the streets dirty". (Photo by Andrea Comas/Reuters)

Visitors walk past "Sculpture #1" by Darren Bader at the Frieze Art Fair in London, Britain October 14, 2015. The Frieze Art Fair, which is one of the world's leading contemporary art fairs, opens today and runs through October 17. (Photo by Suzanne Plunkett/Reuters)

A candle burns during a vigil in Aotea Square to remember victims of the Paris attacks on November 14, 2015 in Auckland, New Zealand. According to reports, over 150 people were killed in a series of bombings and shootings across Paris, including at a soccer game at the Stade de France and a concert at the Bataclan theater. (Photo by Hannah Peters/Getty Images)