Sabera Bayanne, 20, a student of the Shaolin Wushu club, practices in Kabul, Afghanistan January 29, 2017. On a snowy mountaintop to the west of Kabul, a group of Afghan girls practise the flowing movements of Wushu, a sport developed from ancient Chinese kung fu martial arts, stretching and bending and slashing the air with bright swords. (Photo by Mohammad Ismail/Reuters)

A woman wears a face mask in the part of the city near neighbourhoods known for burning coal for heating in Ulaanbaatar, Mongolia January 26, 2017. Not many people in Ulaanbaatar wear masks to protect themselves against pollution. (Photo by B. Rentsendorj/Reuters)

A woman walks up the steps decorated ahead of the Chinese New Year festival in Beijing, China, Thursday, January 12, 2017. The Chinese Lunar New Year is the most important holiday for Chinese and hundreds of millions are expected to return to their hometown to spend the new year with their family and relatives. (Photo by Ng Han Guan/AP Photo)

A protestor gestures toward the White House on the Ellipse near the South Lawn of the White House during the Women's March on Washington January 21, 2017 in Washington, DC. Large crowds are attending the anti-Trump rally a day after U.S. President Donald Trump was sworn in as the 45th U.S. president. (Photo by Drew Angerer/Getty Images)

A boy catches a trout while ice fishing on a frozen river during a fishing contest in Hwacheon, South Korea, Saturday, January 14, 2017. The contest is part of an annual ice festival which draws over 1,000,000 visitors every year. (Photo by /Ahn Young-joon/AP Phot)

A protester wearing a bra and with a message written on her chest can be seen during the first of hundreds of womens' marches organized around the world in a show of disapproval of U.S. President Donald Trump in Sydney, Australia, January 21, 2017. (Photo by Dan Himbrechts/Reuters/AAP)

A dump truck carrying cleaning workers drives on Havana's malecon as a wave crashes on the sea wall, in Cuba, Tuesday, January 24, 2017. Due to high winds and tides, the sea pushed over the sea wall, flooding low parts of the Vedado neighborhood of Havana. (Photo by Desmond Boylan/AP Photo)

A bride waits to take her wedding vow during a mass marriage ceremony in which, according to its organisers, 111 Muslim couples took their wedding vows, in Ahmedabad, India January 26, 2017. (Photo by Amit Dave/Reuters)