Passengers wait for a train to depart from the Hankou Railway Station in Wuhan, central China's Hubei province, Friday January 13, 2017. Officials expect that Chinese travelers will make almost 3 billion trips during the holiday travel rush that starts runs through Feb. 21. These trips include intercity flights, trains and local bus rides to villages for China's 1.4 billion people. (Photo by Chinatopix via AP Photo)

Afghan girl athletes perform Wushu on the top of a hill in Kabul, capital of Afghanistan, January 18, 2017. In the conservative Afghan society where people especially in the countryside deeply believe in the old traditions and don't allow their girls and female members of the family to go out of home, exercising sport in open is extremely risky, but a group of girls are broken the taboo and exercising Wushu on a hilltop where the temperature is minus 2 Celsius degrees. (Photo by Rahmat Alizadah/Xinhua/Barcroft Images)

A Syrian refugee girl cries as she walks through a rainstorm towards Greece's border with Macedonia, near the Greek village of Idomeni, September 10, 2015. Most of the people flooding into Europe are refes fleeing violence and persecution in their home countries who have a legal right to seek asylum, the United Nations said on Tuesday. (Photo by Yannis Behrakis/Reuters)

A worker wearing a protective face mask, cleans up the road in front of a mural in Jakarta, Indonesia, 24 July 2020. Indonesian government has assigned a new team to rebuild the national economy amid the coronavirus pandemic. The country has started to ease COVID-19 lock-down restrictions in an effort to restart the economies and help people in their daily routines after the outbreak of coronavirus pandemic. (Photo by Mast Irham/EPA/EFE)

This aerial photo shows bullet trains parked at a station in preparation for the upcoming Lunar New Year travel peak in Nanjing, in eastern China's Jiangsu province on January 27, 2021, as authorities have encouraged people to stay put during the Spring Festival to curb the spread of of COVID-19 coronavirus. (Photo by AFP Photo/China Stringer Network)

Mother and daughter volunteers Niki, right, and Rachel practice their pancake tossing technique in the streets of Wimborne model town and gardens before taking part in the Wimborne Minster virtual pancake race, in Wimborne, England, Tuesday February 16, 2021. Although a physical race cannot take place this year due to the coronavirus restrictions, Wimborne Minster has invited people to film themselves tossing a pancake for 30 seconds and posting it to Facebook. (Photo by Andrew Matthews/PA Wire via AP Photo)

People wait for Pope Francis to celebrate mass at the Franso Hariri Stadium in Irbil, Kurdistan Region of Iraq, Sunday, March 7, 2021. The Vatican and the pope have frequently insisted on the need to preserve Iraq's ancient Christian communities and create the security, economic and social conditions for those who have left to return (Photo by Andrew Medichini/AP Photo)

Omar Gamal, a 28-year-old pigeon keeper, stands next to his pigeon coop on his rooftop in the Egyptian capital's twin city of Giza on February 21, 2021, with the Pyramids of (R to L) Khufu (Cheops), Khafre (Chephren), and Menkaure (Menkheres) in the background. An ancient tradition handed down through the generations, the practice of domesticating pigeons stretches across borders from the banks of the Nile to north Africa and beyond, with people not only training birds for competitions, but also serving them up as a dining delicacy. (Photo by Khaled Desouki/AFP Photo)