A climate activist wears an oxygen mask to demonstrate the possibility of pumping oxygen from a tree in a bottle in the future, during a protest against the government's deforestation practices of Sri Lanka's main wildlife forests for developments in Colombo, Sri Lanka on March 22, 2021. (Photo by Dinuka Liyanawatte/Reuters)

A woman dressed up for Halloween travels on a Metro train in São Paulo, Brazil on October 30, 2017. (Photo by Cris Faga/Rex Features/Shutterstock)

Indian students smear coloured powder during an event to celebrate the Hindu festival of Holi in Kolkata on February 26, 2018. Holi, the popular Hindu spring festival of colours is observed in India at the end of the winter season on the last full moon of the lunar month, and will be celebrated on March 1 this year. (Photo by Dibyangshu Sarkar/AFP Photo)

Jaime “Ka Diego” Padilla (R), spokesperson of the Melito Glor Command of the New People's Army (NPA), and Ka Kathryn (Comrade Kathryn) (L) react during their 50th founding anniversary celebration at an undisclosed location in the mountains of Sierra Madre, Philippines, 31 March 2019. (Photo by Alecs Ongcal/EPA/EFE)

People celebrate after Gov. Ricardo Rossello announced that he is resigning Aug. 2 after weeks of protests over leaked obscene, misogynistic online chats, in San Juan, Puerto Rico, Thursday, July 25, 2019. (Photo by Carlos Giusti/AP Photo)

Robots serve trays with food to customers waiting at the Robot theme restaurant in Bangalore, India, 17 August 2019. Six robots are deployed as waiters at the the robot-themed Robot restaurant where each table is equipped with a tablet to place one's order. (Photo by Jagadeesh N.V./EPA/EFE)

Two brave contestants take part in the World Gravy Wrestling Championships at the Rose 'n Bowl in Stacksteads, Lancashire, England on August 27 2018. Contestants must wrestle in the gravy for 2 minutes, points are scored for fancy dress, comedy effect, entertainment and wrestling ability. The event is held to raise funds for the East Lancashire Hospice and competitors nominated charities. (Photo by The Mercury Press)

People are captured by FLIR (Forward-Looking Infrared) HD Thermal Imaging Cameras as they walk near the FLIR exhibit at the Las Vegas Convention Center during CES 2019 in Las Vegas on January 10, 2019. (Photo by David McNew/AFP Photo)