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)

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 Thai villager runs with a bullock during a catching a bullock competition as part of the annual bullock cart racing festival in Phetchaburi province, Thailand, 21 February 2016. The annual bullock cart race festival held to celebrate the end of the harvest season. (Photo by Rungroj Yongrit/EPA)

A model presents a creation by Japanese designer Yoshikazu Yamagata for his label writtenafterwards during the Mercedes-Benz Fashion Week in Tokyo, Japan, 16 March 2016. The presentation of the Autumn/Winter 2016 collections runs from 14 to 19 March. (Photo by Kiyoshi Ota/EPA)

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)

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)