A man from Dinka tribe holds his AK-47 rifle in front of cows in a Dinka cattle herders camp near Rumbek, capital of the Lakes State in central South Sudan December 14, 2013. (Photo by Goran Tomasevic/Reuters)

Model mum Valeria Garcia walks Marta Jakubowski's SS19 show wearing world first silent wearable breast pump: Elvie Pump at BFC Show Space on September 14, 2018 in London, England. (Photo by Eamonn M. McCormack/Getty Images for Elvie)

A model presents a creation from the Spring/Summer 2019 Women's collection by British designer Bill Gaytten for John Galliano fashion house during the Paris Fashion Week, in Paris, France, 30 September 2018. (Photo by Julien de Rosa/EPA/EFE)

A migrant boy sits on railway tracks at a train station in Tovarnik, Croatia, September 20, 2015. (Photo by Antonio Bronic/Reuters)

Participants run through the streets of the Back Bay during the 16th annual Santa Speedo Run in Boston, Massachusetts, December 12, 2015. (Photo by Brian Snyder/Reuters)

A girl carries a bag of recyclable items she collected from a landfill on the outskirts of Sanaa, Yemen November 16, 2016. (Photo by Mohamed al-Sayaghi/Reuters)

A Thai traffic security guard wears a Santa Claus costume as he directs the traffic on a street during Christmas celebrations outside a shopping mall in Bangkok, Thailand, 22 December 2015. The campaign of a shopping mall is held to celebrate the upcoming Christmas season and to attract shoppers. (Photo by Narong Sangnak/EPA)