East Berliners crossing into the West Berlin on November 11, 1989 at the Potsdamer Platz, Germany. (Photo by Kai Wiedenhoefer)

A woman wades through a flooded village in the eastern state of Bihar, India August 22, 2017. (Photo by Cathal McNaughton/Reuters)

An undated handout image provided by UNICEF Germany on 20 December 2016 shows the “UNICEF Photo of the Year 2016” by Iranian freelance photographer Arez Ghaderi. Ghaderi won the first prize for his picture of a girl in a makeshift tent city in the Razavi Khorasan province, Iran, it was announced at a ceremony in Berlin, Germany on 20 December 2016. (Photo by Ariz Ghaderi/EPA/UNICEF Deutschland)

A truck driver naps under his truck at the fancy bazaar area during the twelve hours Assam bandh or strike in Guwahati, Assam, India, 23 October 2018. At least 46 organisations are observing a 12-hour bandh across the state to protest against the Centre's bid to clear the Citizenship (Amendment) Bill 2016, in the Winter Session of Parliament. (Photo by EPA/EFE/Stringer)

A young Sikh boy shouts religious slogans during a procession ahead of the birth anniversary of Guru Nanak in Jammu, India, Wednesday, November 21, 2018. The birth anniversary of Guru Nanak, founder of Sikhism and first Sikh guru, will be marked on Nov. 23. (Photo by Channi Anand/AP Photo)

Partygoers in Cardiff, England refused to let the rain dampen their Christmas spirits on “Thirsty Thursday”, December 19, 2018. Christmas partygoers got into the party spirit last night as they headed out for some festive fun up and down the country. (Photo by Huw Evans Picture Agency)

An Army Sikorsky R-5 helicopter, undergoing record trials, demonstrates its lifting power by carrying 17 persons and pilot aloft as female onlookers wave in Bridgeport, Conn., January 10, 1946. During the tests records were claimed for altitude speed and both altitude and speed with payload. (Photo by Anthony Camerano/AP Photo)

Ministry of Defence handout photo of Chinooks from RAF Odiham as they take part in the Royal Air Force flypast over central London to mark the centenary of the RAF on Tuesday, July 10, 2018. (Photo by SAC Pippa Fowles (RAF)/PA Wire)