A Tibetan man stirs butter tea made for the arriving guest during the function organised to mark Losar or the Tibetan New Year at a Tibetan Refugee Camp in Lalitpur February 19, 2015. Tibetans across the world marked the arrival of the New Year with prayers and festivities. (Photo by Niranjan Shrestha/AP Photo)

An undated archive picture shows a dog pulling a Belgian machine gun at an unknown location in northern France. A Viscount in the Armoured Cavalry Branch of the French Army left behind a collection of hundreds of glass plates taken during World War One (WWI) that have never before been published. The images, by an unknown photographer, show the daily life of soldiers in the trenches, destruction of towns and military leaders. The year 2014 marks the 100th anniversary of the start of WWI. (Photo by Collection Odette Carrez/Reuters)

A female rebel in Kabul, Afghanistan, circa 1979. Photo taken at a parade in Kabul in honor of the pro-Communist Saur Revolution. She was from the women’s battalion of the people’s militia (one of the anti-imperial groups that participated in the coup d’etat). (Photo by Viktor Khabarov)

Yang Juan, an employee at Goopal Group, takes a nap in her seat after lunch, in Beijing, China, April 21, 2016. Office workers sleeping on the job is a common sight in China, where a surplus of cheap labour can lead to downtime at work. But in China's technology sector, where business is growing faster than many start-up firms can hire new staff, workers burn the midnight oil to meet deadlines and compete with their rivals. Some companies provide sleeping areas and beds for workers to rest during late nights. (Photo by Jason Lee/Reuters)

A rickshaw puller transports passengers through a water-logged street after heavy rain in Kolkata, India on June 26, 2018. (Photo by Rupak De Chowdhuri/Reuters)

A man rides a horse while others swim on the beach of Gaza City, Friday, August 3, 2018. (Photo by Khalil Hamra/AP Photo)

English singer Victoria Louise “Pixie” Lott attends the launch of the new Pixie Lott Paint collection at The Cuckoo Club on June 27, 2017 in London, England. (Photo by PA Wire)

A truck transporting 20 tons of fish lost its load after crashing on a road near Liepen, eastern Germany on April 20, 2018. (Photo by Stefan Sauer/AFP Photo/DPA)