A military band prepares to play the national anthems before Cuban President Raul Castro welcomes U.S. President Barack Obama at the Palacio de la Revolucion in Havana March 21, 2016. Barack Obama on Sunday became the first US president in 88 years to visit Cuba, touching down in Havana for a landmark trip aimed at ending decades of Cold War animosity. (Photo by Jonathan Ernst/Reuters)

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)

A devotee participates in Holi celebrations at the Nandagram temple, on March 22, 2013. (Photo by Manish Swarup/Associated Press)

A picture taken on July 14, 2014 from a Boeing C135 refueling tanker shows two French Rafale fighter planes, flying over the French capital during the annual Bastille Day military parade on the Champs-Elysees in Paris. France has issued an unprecedented invitation to all 72 countries involved in World War I to take part in its annual Bastille Day military parade. (Photo by Franck Pennant/AFP Photo)

American Yoga teacher Dashama poses on a Yoga-board during a preview of the 46th International Boat Fair in Duesseldorf January 16, 2015. The BOOT 2015 watersports fair, with more than 1,600 international exhibitors will run in Duesseldorf from January 17 to January 25. (Photo by Ina Fassbender/Reuters)

In this July 11, 2018 photo, members of a private photo studio take pictures of a woman in Havana, Cuba. New rules for private business indicate that the government has ruled out going further to open private business, such as allowing small and medium enterprises and authorizing business to operate as societies. Currently, private business licenses are granted only to individuals, and only one license per person. (Photo by Desmond Boylan/AP Photo)

A visitor looks at portraits of Mao Zedong amid his statues on display at a wholesale souvenir store in Shaoshan, Hunan Province in central China, 28 April 2016. Shaoshan is the hometown of former Communist leader Mao Zedong, popularly known as Chairman Mao. Thousands of visitors descend on this small Chinese town burrowed in the hills of Central China's Hunan province to pay homage to the “Great Helmsman” everyday. It is one of the core sites of the “Red Tourism” industry, where communist party cadres and ordinary Chinese tourists alike seek to relive the experiences and rekindle the spirit of the revolutionaries. (Photo by How Hwee Young/EPA)

The Apple l, the first Apple computer made by Steve Jobs and Steve Wozniak in 1976, is seen on display at Sotheby's on June 8, 2012 in New York City. Sotheby's called the computer “an exceptionally rare, working example with original Apple cassette interface, operation manuals and a rare BASIC Users' Manual”. (Photo by Andrew Burton/AFP)