Some of London's telephone operators and engineers, trying out their gas masks at the anti-gas civilian training centre in Gloucester, where they were taught how to deal with gas attacks. (Photo by Harry Todd/Fox Photos/Getty Images). 13th February 1937

In this Sunday, March 5, 2017 photo, hospitality staff pose for photos on Tiananmen Square during the National People's Congress held at the Great Hall of the People in Beijing. (Photo by Andy Wong/AP Photo)

A five-week-old orphaned Southern Sea Otter pup rests on a rubber mat after arriving at the Shedd Aquarium's Abbott Oceanarium in Chicago, Illinois October 28, 2014 in this handout photo provided to Reuters on November 5, 2014. The stranded pup was found on September 30 on Coastways Beach in California and was rescued the next day to be brought back to health at the Monterey Bay Aquarium. Southern sea otters were listed as “threatened” under the U.S. Endangered Species Act in 1977. (Photo by Brenna Hernandez/Reuters/Shedd Aquarium)

A pro-democracy protester wears a hat in the shape of a yellow rubber duck, which has become a recent symbol for the ongoing protests, during an anti-government rally in Bangkok on November 22, 2020. (Photo by Lillian Suwanrumpha/AFP Photo)

A woman wears a Yao bridal headdress in Hezhou, Guangxi, China on January 6, 2021. (Photo by Sipa Asia/Rex Features/Shutterstock)

A woman walks up a stairway painted in the rainbow colors in Bucharest, Romania, Saturday, July 11, 2020. Romania reported 698 new COVID-19 infections in the last 24 hours, the highest level since the pandemic reached the country in February. (Photo by Vadim Ghirda/AP Photo)

A young girl from the Makonde ethnic group wearing earth makeup on her facen, a beauty symbol, carries a baby on her back as she poses for pictures in the community of Marupa, a relocation center for internally displaced families in the Chiure district, on February 23, 2021. Thousands of families from different districts of the Cabo Delgado province who have been displaced have been located by the government in different areas of the province. (Photo by Alfredo Zuniga/AFP Photo)

Hindu married women offer prayers and tie a thread around a banyan tree during the festival of Vat Purnima amid the spread of the coronavirus disease (COVID-19), in Mumbai, India, June 24, 2021. (Photo by Francis Mascarenhas/Reuters)