Medic James E. Callahan of Pittsfield, Mass., gives mouth-to-mouth resuscitation to a dying soldier in war zone D, about 50 miles northeast of Saigon, June 17, 1967. Thirty-one men of the 1st Infantry Division were reported killed in the guerrilla ambush, with more than 100 wounded. (Photo by Henri Huet/AP Photo)

Children of the Roma community play as they cool off in a fountain in the main square of Pristina, Kosovo on June 14, 2017. (Photo by Armend Nimani/AFP Photo)

Public Space series, 2015. This series by Morteza Niknahad and Behnam Zakeri tends toward cinema, taking an almost cartoonish view of modern life in Iran. This work was inspired by the social life of dolphins. (Photo by Morteza Niknahad and Behnam Zakeri/The Guardian)

A cyclist drives past a flowering rapeseed field not far from the small Bavarian village of Schoengeising, near Munich, during a nice, warm sunny weather day on May 17, 2017. (Photo by Christof Stache/AFP Photo)

A child dressed as Hindu God Shiva begs for alms from devotees at the Sangam, the confluence of three rivers – the Ganges, the Yamuna and the mythical Saraswati, on the Makar Sankranti festival during the annual traditional fair of Magh Mela in Prayagraj, in the northern Indian state of Uttar Pradesh, Sunday, January 14, 2024. Hundreds of thousands of Hindu pilgrims are expected to take dips in the confluence, hoping to wash away sins during the month-long festival. (Photo by Rajesh Kumar Singh/AP Photo)

People kiss before the start of the Carmelitas street party on the first day of Carnival in Rio de Janeiro, Brazil, Friday, February 9, 2024. (Photo by Bruna Prado/AP Photo)

Revellers brave the chill and jump into the water at Carnlough, Co. Antrim, Northern Ireland on January 1, 2024. (Photo by Arthur Allison/Pacemaker)

Revellers brave the rain as they make the most of New Year's Eve in Liverpool city centre, United Kingdom on December 31, 2023. (Photo by Ioannis Alexopoulos/London News Pictures)