Alex Plunkett, left, and Sean Hart, both of Arlington, Va., join hundreds participating in the annual International Pillow Fight Day on April 5. Massive pillow fights broke out on the Mall in Washington and in cities around the world. (Photo by Marvin Joseph/The Washington Post)

A Japanese girl participates in a calligraphy contest to the celebrate the New Year in Tokyo January 5, 2015. Over 3,000 calligraphers, having qualified in country wide competitions throughout Japan, took part in the annual contest to celebrate the new year. (Photo by Issei Kato/Reuters)

The Jet Propulsion Lab team's RoboSimian robot turns on a valve at a simulated disaster-response course during day one of the Defense Advanced Research Projects Agency (DARPA) Robotics Challenge finals in Pomona, California, June 5, 2015. (Photo by David McNew/Reuters)

A couple take photographs alongside the National Monument on Calton Hill, Edinburgh on Wednesday January 5, 2022, ahead of First Minister Nicola Sturgeon's update to the Scottish Parliament on the Covid-19 situation as the Omicron variant sweeps across the country. (Photo by Jane Barlow/PA Images via Getty Images)

In this picture taken on January 5, 2022, people take part in a demonstration march after the Pyongyang City rally to carry out the decision of the 4th Plenary Meeting of the 8th Central Committee of the Workers' Party of Korea, at Kim Il Sung Square in Pyongyang. (Photo by Kim Won Jin/AFP Photo)

Girls in Han costumes pose for a photo with blooming cherry blossoms at Yuyuantan Park during Qingming Festival holiday on April 4, 2022 in Beijing, China. Qingming Festival, also known as Tomb Sweeping Day, falls on April 5 this year. (Photo by Zhao Naiming/VCG via Getty Images)

Su-25 jet fighters release smoke in the colours of the Russian state flag over Red Square during a flypast rehearsal ahead of a parade on Victory Day, which marks the anniversary of the victory over Nazi Germany in World War Two, in Moscow, Russia on May 5, 2021. (Photo by Shamil Zhumatov/Reuters)

A confiscated pet lion poses with a dog as it arrived back home from the Phnom Tamao Wildlife Rescue Center after Prime Minister Hun Sen ordered authorities to return the animal in Phnom Penh, Cambodia, July 5, 2021. (Photo by Cindy Liu/Reuters)