The “EMIEW3” robot (R) demonstrates communicating with a visitor during a press preview in Tokyo on April 8, 2016. Japanese electronics giant Hitachi unveiled its humanoid customer service and guidance robot “EMIEW3” and “remote brain” robotics IT platform. (Photo by Toshifumi Kitamura/AFP Photo)

Hotel staff practice self-defence skills after a training session given by team member of Special Weapons and Tactics (SWAT) team, in Hangzhou, Zhejiang province, April 7, 2016. (Photo by Reuters/Stringer)

South Sudanese wrestlers take part in a wrestling match for peace in Juba on April 19, 2016. The last wrestling match for peace was held in Juba the day before civil war broke out in December 2013. (Photo by Carl de Souza/AFP Photo)

Joshua Patino stands on a ladder to put finishing touches on a giant dinosaur exhibit at PAX East in the Boston Convention and Expo Center, Thursday, April 21, 2016, in Boston. PAX East, an annual celebration of gaming culture, is expected to draw tens of thousands of visitors Friday through Sunday. It's a place where serious gamers can preview unreleased video games and devices, compete in tournaments, hear live music and meet others for whom gaming is a way of life. (Photo by Elise Amendola/AP Photo)

Taiwanese-US artist Chin Chih Yang poses for a photograph with 30,000 aluminum cans after his performance called “Kill Me or Change” in Taipei, Taiwan, 23 April 2016. “Kill Me or Change!” is a performance piece that aims to raise awareness of the benefits of recycling and, encourage people to recycle to conserve resources. (Photo by Ritchie B. Tongo/EPA)

Models display a creation by K-Lynn Lingerie during a fashion show in the Lebanese capital Beirut on April 24, 2016. (Photo by Anwar Amro/AFP Photo)

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)

Fabian Ramirez, 11, scavenges a trash container for vegetables with his family that were discarded at the “Mercado de Abasto”, a market for vendors, during the fourth week of a quarantine to help contain the spread of the new coronavirus in Asuncion, Paraguay, Thursday, April 2, 2020. (Photo by Jorge Saenz/AP Photo)