In this photograph taken on February 18, 2016, Pakistani children ride on swings in the predominantly Pashtun Korangi District of Karachi. In a rundown district of Karachi, Rabia balks at a neighbour's proposal to vaccinate her children, demonstrating one of the biggest hurdles to eradicating polio in Pakistan by the end of the year: confused and frightened parents. (Photo by Asif Hassan/AFP Photo)

People carry drinks at 80s Bar in Damascus, Syria, March 11, 2016. In Damascus's Old City, just a mile from the battered frontline between government and rebel-held territory, young Syrians smoke, drink beer or soft drinks, and talk about anything but the war. The revival of activity in this once-vibrant quarter is part of efforts to project an air of normality in the Syrian capital, even as the five-year-old war that has killed more than 250,000 people and created 5 million refugees continues to rage nearby. (Photo by Omar Sanadiki/Reuters)

Aerial view of tourists in life vests and rubber rafts in the Grand Canyon of western Henan, Sanmenxia, China on August 5, 2017. (Photo by Imaginechina/Rex Features/Shutterstock)

A “super blood blue moon” is seen during an eclipse behind an elephant statue at a temple in Bangkok, Thailand, January 31, 2018. (Photo by Athit Perawongmetha/Reuters)

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)

Women jump as they pose for photo in front Patuxay park, ahead of the ASEAN Summit in Vientiane, Laos September 5, 2016. (Photo by Soe Zeya Tun/Reuters)

A woman crosses a road outside the EU Parliament ahead of the EU elections in Brussels, Belgium, May 22, 2019. (Photo by Yves Herman/Reuters)

A young USA fan smiles ahead of the 2019 Concacaf Gold Cup semifinal football match between USA and Jamaica on July 3, 2019 in Nashville, Tennessee. (Photo by Ricardo Arduengo/AFP Photo)