Miniature pig “Nueffel” is walked in a park in Hanover, Germany, 14 April 2016. (Photo by Sebastian Gollnow/EPA)

People walk during a polluted day in Shenyang, Liaoning province, March 31, 2016. (Photo by Reuters/Stringer)

A competitor walks on tightrope during a performance in Taizhou, Zhejiang Province, China, May 7, 2016. (Photo by Reuters/China Daily)

People walk with their arms raised as security forces restore order in Nice, France on July 14, 2016. (Photo by SIPA Press/Rex Features/Shutterstock)

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)

People walk on the street in Samara, Russia on July 18, 2017. (Photo by David Mdzinarishvili/Reuters)

Residents walk past electoral posters in Port-au-Prince, Haiti, January 28, 2017. (Photo by Andres Martinez Casares/Reuters)

People dressed as zombies take part in a “Zombie Walk” parade in Athens, Greece, February 25, 2017. (Photo by Michalis Karagiannis/Reuters)