A housewife whose family lives in a shanty cooks beside a road in Manila, Philippines May 25, 2016. (Photo by Erik De Castro/Reuters)

An African giant pouched rat sniffs for traces of landmine explosives at APOPO's training facility in Morogoro on June 17, 2016. APOPO trains the rats to detect both tuberculosis and landmines at its facility. Every year landmines kill or maim thousands of people worldwide. The trained rats sniff for explosive and so are able to detect the presence of landmines far faster than conventional methods which involve metal detection. (Photo by Carl De Souza/AFP Photo)

A traffic police officer directs vehicles at a street junction during sunset in Pyongyang, North Korea, Thursday, August 25, 2016. (Photo by Dita Alangkara/AP Photo)

A lone male cheetah is set upon by a pack of African wild dogs. Peter Haygarth had been following the dogs as they hunted in Zimanga Private Game Reserve in KwaZulu-Natal, South Africa. On first encountering the cheetah, the dogs were wary, but as the rest of the pack arrived, their confidence grew and they began to encircle the cat. Peter kept his focus on the cat’s face. In a few minutes the spat was over as the cheetah fled. (Behaviour: mammals category). (Photo by Peter Haygarth)

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)

A man sits next to a damaged idol of Hindu goddess Kali which was taken out after its immersion in the river Ganges in Haridwar, India, March 29, 2017. (Photo by Danish Siddiqui/Reuters)

Ammunition airlift into besieged Khe Sanh, Operation Pegasus, April 1968. (Photo by Larry Burrows/AP Photo)

In this July 20, 2018 photo, Joshep Balta, a clown named “Cachupito”, peers through the tent curtain to see how many people are waiting for the show, put on by the International Circus, set up in the shanty town of Puente Piedra on the outskirts of Lima, Peru. Balta, a 12-year old clown whose parents work at the circus setting up and breaking down the encampment, was discovered by the circus two years ago when he was performing as a clown at street corners. (Photo by Martin Mejia/AP Photo)