Visitors hold ice blocks to cool themselves in hot weather at a water park on June 23, 2016 in Chongqing, China. Citizens and visitors escaped high temperature at a water park in Yangren Jie (also known as Foreigner Street), Nan'an District of south China's Chongqing. (Photo by VCG/VCG via Getty Images)

Festival goers dance during Glastonbury Festival at Worthy Farm, near Pilton, Somerset, Britain, 23 June 2017. The outdoor festival runs from 21 to 25 June. (Photo by Nigel Roddis/EPA)

A polar bear fast asleep at London Zoo. (Photo by Fox Photos/Getty Images). 1961

Judy, a black collie whose owner was killed by a train when trying to retrieve her after she slipped her lead. (Photo by Evening Standard/Getty Images). 17th December 1976

Ali al-Naami, convicted of murdering his three daughters, is placed on a carpet to be executed at a public square in Sana'a, Yemen, 16 June 2021. Defendant Ali al-Naami, 40, convicted of killing his daughters Rahaf, 7, Raghad, 12, and Malak, 14, in June 2019, was executed by an executioner in front of hundreds of spectators in a public square in Sana'a. He had admitted to strangling them and drowning them in a water tank after the mother left the house due to domestic disputes with him. (Photo by Yahya Arhab/EPA/EFE)

Roped up climbers leave the summit of Breithorn at 4,164 metres (13,661 feet) on the ridge marking the border with Switzerland (left) and Italy in the Alpine resort of Zermatt August 4, 2014. Switzerland will vote on November 30 on an initiative from the group Ecopop which proposes a cap on the number of immigrants. The group says it is motivated by concerns about a lack of living space exerting too much pressure on the land and natural resources, rather than by opposition to foreigners. (Photo by Denis Balibouse/Reuters)

In Omdurman, the largest city in Sudan, the Qadiriyya Sufi order meets every Friday outside Sheikh Hamed Al Nil mosque, which houses the tomb of their 19th century Sufi leader. (Photo by Ala Kheir, John Burns and Ibrahim Algrefwi/Brownbook)

This picture taken on June 1, 2019 shows Alex Gao trying to balance a book on his head during an etiquette and manners class in central Shanghai. Against a soundtrack of classical music, children learn social skills, dining manners and deportment in the class, which costs $390 for four hours of practical instruction per student. (Photo by Hector Retamal/AFP Photo)