Circus performer from the Association of Circus Proprietors on Whitehall, London, Britain, 07 July 2020. The association handed a petition to Downing Street to ask British Prime Minister Boris Johnson to allow circuses to reopen. (Photo by Will Oliver/EPA/EFE)

A prong extending from a remote-controlled robot prototype approaches the mouth of a volunteer to extract a throat swab sample, as part of a self-funded project to assist physicians in running tests on suspected COVID-19 coronavirus patients in a bid to limit human exposure to disease-carriers, at a private hospital in Egypt's Nile delta city of Tanta, on March 20, 2021. (Photo by Khaled Desouki/AFP Photo)

United States Air Force Academy graduates cheer as the United States Air Force Thunderbirds fly over the graduation for the Class of 2021 at Falcon Stadium on May 26, 2021 in Colorado Springs, Colorado. Chairman of the Joint Chiefs of Staff General Mark A. Milley gave the commencement address to the 1,019 graduates from the academy. (Photo by Michael Ciaglo/Getty Images)

American singer and rapper Ashton Nicole Casey, known professionally as Ashnikko performs on Day 2 of Leeds Festival 2021 at Bramham Park on August 28, 2021 in Leeds, England. (Photo by Matthew Baker/Getty Images)

A 2 year old cattle dog emerges from the water after retrieving a ball during the 2nd Annual Rio Grande Doggy Paddle held at the Rio Grande Pool, Albuquerque, New Mexico, USA on September 12, 2021. (Photo by Adolphe Pierre-Louis/Albuquerque Journal via ZUMA/Rex Features/Shutterstock)

Journeys and adventures winner – This is My Jungle. A wild elephant attacks a jeep full of people. “We should respect nature and care more about it, but we should also avoid taking unnecessary and reckless risks”. (Photo by Savvi Sergey/SIPA Contest)

Soldier boys at Fort Dix, N.J., learn something about guns during their working hours, as they show their girlfriends at a camp dance, December 13, 1940. In front row, playing with the coin amusement gun, from left: Pvt. Tom D'Amato of West Orange; Rose Sinkewicz, behind gun site, of Trenton; Julia Ivans of Trenton, and Pvt. Vernon Landers of Kearney. Back row: Pvts. William Sargent and William Corlies of Philadelphia. (Photo by AP Photo)

Train attendants take part in a parade training as they visit the national flag guard during a patriotic education event ahead of the 90th anniversary of the founding of the Chinese People's Liberation Army (PLA) in Beijing, China July 25, 2017. (Photo by Reuters/China Stringer Network)