A priest is seen looking out of Abuna Yemata church’s only window. Priests cheerfully tell visitors that pregnant women, babies and old people attend Sunday services and no one has fallen off. (Photo by Ethiopia – The Living Churches of an Ancient Kingdom/The American University in Cairo Press/The Guardian)

Joseph Szabo was a frustrated high-school teacher in need of inspiration – so he started photographing his students, and captured all the angst and excitement of being caught between childhood and adulthood. Here: “Priscilla”, 1969. (Photo by Joseph Szabo/Courtesy of Michael Hoppen Gallery/The Guardian)

Farmer Zhang Xianping rides his pig "Big Precious" during an interview with the media, in Zhangjiakou, Hebei province, China, November 2, 2015. Zhang, a pig breeder, instead of killing it, decided to keep the two-year-old "Big Precious" as pet when its weight reached 600 kg, according to local media. (Photo by Reuters/China Daily)

Visitors wear shirts with an image of former Chinese leader Mao Zedong at the Shanghai World Expo site in Shanghai, May 2, 2010. (Photo by Aly Song/Reuters)

People perform during this year's flashmob of silly walks, based on the sketch from the television show Monty Python's Flying Circus by Monty Python troup, in Budapest, Hungary, 01 April 2019. (Photo by Zoltán Balogh/EPA/EFE)

A Palestinian horseman rides on the beach at sunset a few hours prior to the new year's celebrations, west of in Gaza city on December 31, 2018. (Photo by Mahmud Hams/AFP Photo)

People take photos with the skyline of the central business district in Singapore on September 10, 2015. (Photo by Edgar Su/Reuters)

Pakistani vendors carry animals in a bus for the upcoming Muslim festival Eid al-Adha in Lahore, Pakistan, Monday, August 5, 2019. Eid al-Adha, or Feast of Sacrifice, is the most important Islamic holiday and marks the willingness of the Prophet Ibrahim (Abraham to Christians and Jews) to sacrifice his son. (Photo by K.M. Chaudhry/AP Photo)