An Indian labourer sifts coloured powder, known as “gulal”, to be used during the forthcoming spring festival of Holi, inside a factory at Fulbari village on the outskirts of Siliguri on March 6, 2017. Holi, the popular Hindu spring festival of colours is observed in India at the end of the winter season on the last full moon of the lunar month, and will be celebrated on March 13 this year. (Photo by Diptendu Dutta/AFP Photo)

North Korean commuters are seen through a door window waiting to board a train in a subway train station in Pyongyang, North Korea, 14 April 2017. North Koreans are preparing to celebrate the “Day of the Sun” festival, commemorating the 105th birthday anniversary of former supreme leader Kim Il-sung on 15 April, as tension over nuclear issues rise in the region. (Photo by How Hwee Young/EPA)

A guard secures gates of a catfish farm visited by a group of foreign reporters in Pyongyang, North Korea April 17, 2017. (Photo by Damir Sagolj/Reuters)

An artist airbrushes a model during the “World Bodypainting Festival 2017” in Klagenfurt, Austria on July 28, 2017. (Photo by Leonhard Foeger/Reuters)

A tourist train is decorated with Christmas lights in Bogotá, Colombia on December 10, 2017. (Photo by Jaime Saldarriaga/Reuters)

Two women kiss each other during a flashmob on the ocassion of the International Day Against Homophobia, Transphobia and Biphobia in Pamplona, Navarra, Spain, 17 May 2017. The International Day Against Homophobia, Transphobia and Biphobia is held every year on 17 May. (Photo by Villar Lopez/EPA/EFE)

A reveller of the Salgueiro samba school performs during the second night of Rio's Carnival at the Sambadrome in Rio de Janeiro, Brazil, on February 13, 2018. (Photo by Mauro Pimentel/AFP Photo)

British theoretical physicist Stephen Hawking, Cambridge University Professor and Fellow, circa 1985. Stephen Hawking, the brightest star in the firmament of science, whose insights shaped modern cosmology and inspired global audiences in the millions, has died aged 76. (Photo by Gemma Levine/Getty Images)