This picture taken on March 1, 2016 shows a man running a mobile pig mating service and waiting outside a customer's home with his male pig in a cage pulled behind his motorcycle in the northern province of Bac Ninh. (Photo by Hoang Dinh Nam/AFP Photo)

Workers carve ice art works at Harbin Ice and Snow World one day before the 32th Harbin International Ice and Snow Festival in Harbin city, China's northern Heilongjiang province, 04 January 2016. The festival will run from 05 January to 05 February. (Photo by Wu Hong/EPA)

British band Florence and the Machine performs at the Bilbao BBK Live festival in Bilbao, Spain, early 13 July 2018. Bilbao BBK Live festival runs from 12 July to 14 July 2018. (Photo by Miguel Tona/EPA/EFE)

Women wearing Dirndl, a traditional Alpine folk dress, run to get a place in a tent for the opening of the 185th Oktoberfest beer festival in Munich, Germany, 22 September 2018. The Oktoberfest lasts until October 7 and is the world's largest beer festival. The beer festival typically draws over six million visitors. (Photo by Karl- Josef Hildenbrand/DPA/Alamy Live News)

Comic Con fans in costume arrive for the 1st day of the 2018 New York Comic-Con at the Jacob Javits Center on October 4, 2018. The four-day event which runs October 4-7 is the largest pop culture event on the East Coast. (Photo by Timothy A. Clary/AFP Photo)

A young boy scavenges for re-sellable items from garbage on the streets, runs past a sign showing incumbent President Muhammadu Buhari, left, and local party official Mustapha Dankadai, right, in Kano, northern Nigeria Friday, February 15, 2019. (Photo by Ben Curtis/AP Photo)

Festival goers pose for photographers on the third day of Glastonbury Festival at Worthy Farm, Somerset, England, Friday, June 28, 2019. Temperatures are expected to soar over the weekend as a heatwave hits parts of Europe, while the festival runs for five days and is one of the largest events of its kind in the world. (Photo by Joel C. Ryan/Invision/AP Photo)

A robot is seen on Mount Etna, Italy on July 4, 2017. Mount Etna, in Sicily, is a test bed for the approximately three-foot high, four-wheeled machine ahead of a future mission to the moon. It is being conducted by the German Aerospace Centre, the agency which runs Germany's space programme. (Photo by Antonio Parrinello/Reuters)