Students from CAS Ballet Theatre School stretch on the sidewalk Saturday, February 20, 2016, in Ann Arbor, Mich. (Photo by Junfu Han/The Ann Arbor News via AP Photo)

Dajana Djuric, 25, who has worked as a chimney sweep since the age of six, cleans a chimney in Brcko, Bosnia and Herzegovina. Dajana Djuric, believed to be the only female chimney sweep in Bosnia and Herzegovina, has to contend with perilous roofs in the depth of winter. (Photo by Dado Ruvic/Reuters)

Former NBA player Yao Ming (R), a member of the 12th Chinese People's Political Consultative Conference (CPPCC) National Committee, is seen during an interview in Beijing, China, in this picture taken March 9, 2016. (Photo by Reuters/China Daily)

Women take a selfie next to a police officer as they take part in New Year's Eve celebrations in the Bund, in Shanghai, China December 31, 2016. (Photo by Aly Song/Reuters)

A Hindu pilgrim feeds biscuits to an ox to seek blessing before heading for an annual trip to Sagar Island for the one-day festival of “Makar Sankranti”, in Kolkata, India January 10, 2017. (Photo by Rupak De Chowdhuri/Reuters)

Female police officers from Istanbul's Motorcycled Police Unit wait to search vehicles during a roadside checkpoint operation on March 7, 2017 in Istanbul, Turkey. The rapid response unit nicknamed Dolphins is used primarily in crime prevention operations and has 25 female officers. 6% of Turkey's 250,000 strong police force are women, March 8 marks International Women's Day. (Photo by Chris McGrath/Getty Images)

North Korean soldiers keep watch at the bank of the Yalu River, near the North Korean town of Sinuiju, opposite Dandong in China's Liaoning province, September 10, 2016. (Photo by Thomas Peter/Reuters)

Children, some in tears, are escorted down a road in Barcelona, Spain, Thursday, August 17, 2017. Police in Barcelona say a white van has mounted a sidewalk, struck several people in the city's Las Ramblas district. (Photo by Manu Fernandez/AP Photo)