Protesters clash with police at Speakers Corner as thousands attend Unite For Freedom Against COVID-19 passports and vaccines in London, UK on April 24, 2021. People called online to a flash mob-style mass gathering against vaccine passport, face masks and lockdown. The government aims to provide official proof of vaccination for millions of British holidaymakers this summer starting as early as 17 May. (Photo by World Entertainment News Network)

A man smokes a marijuana cigarette to celebrate 420, in Times Square amid the coronavirus disease (COVID-19) pandemic in New York City, New York, U.S., April 20, 2021. (Photo by Carlo Allegri/Reuters)

Members of the special operations team conduct a building climbing training in Qinzhou, south China's Guangxi Zhuang Autonomous Region, April 13, 2021. (Photo credit should read Costfoto/Barcroft Media via Getty Images)

An Iranian girls a bag of goldfish ahead of Nowruz, the Iranian New Year, in Tehran, Iran on March 17, 2021. (Photo by Majid Asgaripour/WANA (West Asia News Agency) via Reuters)

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)

Members of the SubCielo company perform during the fifth annual Puerto Rico Circo Fest in San Juan, Puerto Rico, Saturday, March 10, 2018. The festival is held simultaneously in several spots on the streets of the Old San Juan city on March 10–11. (Photo by Ricardo Arduengo/AFP Photo)

British theoretical physicist Stephen Hawking, Cambridge University Professor and Fellow, circa 1985. Stephen Hawking, the brightest star in the firmament of science, whose insights shaped modern cosmology and inspired global audiences in the millions, has died aged 76. (Photo by Gemma Levine/Getty Images)

A Chinese tourist visits the Mutianyu Great Wall covered in snow on February 23, 2021 in Beijing, China. Affected by the new coronavirus (COVID-19), the number of visitors to Mutianyu Great Wall in 2020 dropped by about 60%. (Photo by Lintao Zhang/Getty Images)