In this September 4, 1963, file photo, a police officer carries off a demonstrator holding a Confederate flag after a group of demonstrators protested enrollment of two African-Americans at Ramsay High School in Birmingham, Ala. The Confederate battle flag has been removed from South Carolina's Statehouse grounds, in the wake of the massacre of nine African-Americans, including a state senator, at an historic black church in Charleston in June 2015. (Photo by AP Photo)

A baby dives as his mother holds on tightly during a water baby class in Odessa, Ukraine on August 6, 2016. (Photo by Andrey Nekrasov/Barcroft Images)

Blossoms and dust are blown by the wind as Jasmin Ricks, left, and her sister, Jessica Ricks, center, take in the cherry blossoms near the Tidal Basin in Washington on April 12, 2018. (Photo by Matt McClain/The Washington Post)

A girl stretches next to a pram on the embankment of the Moskva river in Moscow on October 18, 2018. The European part of Russia enjoys an unusually warm weather for the season with temperatures reaching up to 22 degrees centigrade. (Photo by Mladen Antonov/AFP Photo)

Daniel Cheong, a dog behaviorist and trainer, steps over a leash as he walks a pack of dogs in Arlington, Va. on November 13, 2018. (Photo by Ricky Carioti/The Washington Post)

Five-year-old sniffing dog “Vine” wears protection goggles against the sun and dust as he poses together with Giulia Gausemann for photographers, at the sniffing dogs school of the German Army (Bundeswehr) in Daun, Germany, July 24, 2020. The Bundeswehr sniffing dogs school and the veterinarian university of Hanover are developing a training programme to sniff out the coronavirus disease (COVID-19) with dogs at airports, border crossings and other highly frequented places. (Photo by Wolfgang Rattay/Reuters)

Advanced Space Suit Engineer at NASA Kristine Davis wears the xEMU prototype space suit for the next astronaut to the moon by 2024, during its presentation at NASA headquarters in Washington, U.S., October 15, 2019. (Photo by Carlos Jasso/Reuters)

LiLou the therapy pig stands in front of a departures board at San Francisco International Airport in San Francisco, California, U.S. October 4, 2019. (Photo by Jane Ross/Reuters)