Women in costumes walk as they participate in Halloween celebrations in the downtown of Seoul, South Korea, October 31, 2015. (Photo by Kim Hong-Ji/Reuters)

Demonstrators wear skull masks during an anti government protest, as Chile's President Michelle Bachelet delivers a speech inside the National Congress, in Valparaiso city, Chile May 21, 2016. (Photo by Ivan Alvarado/Reuters)

Members of a teenage girl gang convincing an unwilling recruit to join the gang, circa 1955. (Photo by Vecchio/Three Lions)

Labourers who work nearby nap on a road as cars drive past in Chongqing Municipality, July 23, 2013. (Photo by Reuters/Stringer)

Pro-government fighters stand next to a tank destroyed during recent fighting in Yemen's southwestern city of Taiz March 14, 2016. (Photo by Anees Mahyoub/Reuters)

Angele Blank, right, and Virginia Promeyrat wait for the start of the Greenwich Village Halloween Parade, Saturday October 31, 2015, in New York. (Photo by Tina Fineberg/AP Photo)

Young Japanese women pose with a green bear costumed person during the 'Earth Parade 2015' in Tokyo, Japan, Saturday, November 28, 2015. Ahead of the U.N. climate change summit in Paris starting this week, about 1,000 citizens and environmental activists took to the streets of Tokyo on Saturday, calling for strong actions to combat global warming. (Photo by Franck Robichon/EPA)

A couple lights a lantern during a celebration, known as “Chaharshanbe Souri”, or Wednesday Feast, marking the eve of the last Wednesday of the solar Persian year, Tuesday, March 19, 2019, in Tehran, Iran. Iran's many woes briefly went up in smoke on Tuesday as Iranians observed a nearly 4,000-year-old Persian tradition known as the Festival of Fire. (Photo by Ebrahim Noroozi/AP Photo)