An Iraqi Shi'ite boy poses for a photograph as Iraq Shi'ite Muslims commemorate Ashura in Baghdad, October 24, 2015. Ashura, which falls on the 10th day of the Islamic month of Muharram, commemorates the death of Imam Hussein, grandson of Prophet Mohammad, who was killed in the seventh century battle of Kerbala. (Photo by Ahmed Saad/Reuters)

A girl poses in her costume during a Halloween party at a mall in Quezon city, Metro Manila October 24, 2015. (Photo by Ezra Acayan/Reuters)

Singer Beyonce arrives at TIDAL X: 1020 Amplified by HTC at the Barclays Center on Tuesday, October 20, 2015, in New York. (Photo by Evan Agostini/Invision/AP Photo)

Models get prepared backstage before Wagner Kallieno Winter Collection 2016 show during Sao Paulo Fashion Week in Sao Paulo, Brazil, October 23, 2015. (Photo by Paulo Whitaker/Reuters)

An idol of Hindu goddess Durga floats in water as devotees immerse the same in the River Kuakhai after the Durga Puja festival in Bhubaneswar, India, Saturday, October 24, 2015. The immersion of idols marks the end of the festival that commemorates the slaying of a demon king by lion-riding, 10-armed goddess Durga, marking the triumph of good over evil. (Photo by Biswaranjan Rout/AP Photo)

The six-months-old female koala cub holds on to the back of zoo keeper Lena at the zoo in Duisburg, Germany, 23 October 2015. The yet unnamed baby weighs 580 grams. (Photo by Roland Weihrauch/EPA)

A Russian ground staff member signals to the pilot of a Sukhoi Su-25 fighter jet at the Hmeymim air base near Latakia, Syria, in this handout photograph released by Russia's Defence Ministry October 22, 2015. (Photo by Reuters/Ministry of Defence of the Russian Federation)

Ray Yang, a celebrity trainer, takes a selfie before the start of a workout session during TV program "The Body Show" at a gym in Seoul, September 19, 2015. Looks no longer centre only on the face in beauty-obsessed South Korea, where more women are hitting the gym to improve muscle tone and physical health. As the ideal of beauty evolves in a country that is a trendsetter in cosmetics and the pursuit of plastic surgery, women's fitness has become a growth business, say purveyors of health products, from diet supplements to dumb-bells. (Photo by Kim Hong-Ji/Reuters)