Indian students play with coloured powders as they celebrate “holi” or the “festival of colours” during a special function in Kolkata on March 12, 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 Dibyangshu Sarkar/AFP Photo)

Racegoers in fashionable hats attend Ladies Day at Cheltenham Festival on March 15, 2017 in Cheltenham, England. (Photo by David Davies/PA Wire)

Female soldiers march in formation in St Petersburg' s Palace Square during a rehearsal of a Victory Day military parade marking the 72 nd anniversary of the victory over Nazi Germany in the 1941-1945 Great Patriotic War, the Eastern Front of World War II, on May 5, 2017. (Photo by Peter Kovalev/TASS)

An operator adjusts a film projector during a wedding party in Bogor, Indonesia, February 18, 2017. Indonesian entrepreneur Kamaluddin loves the gritty look of old 35-millimeter film so much that he spends most of his nights screening vintage movies at weddings and parties around Jakarta, the capital. (Photo by Reuters/Beawiharta)

A reveler and a child street vendor pose for a photo during the Banda de Ipanema Carnival parade in Rio de Janeiro, Brazil, Saturday, January 31, 2015. Rio's over-the-top Carnival is the highlight of the year for many local residents. Hundreds of thousands of merrymakers are beginning to take to the streets in open-air “blocos” parties. (Photo by Silvia Izquierdo/AP Photo)

People take pictures and Buddhist monk chants as a groom and a bride lay inside a pink coffin during their wedding ceremony at Wat Takien temple in Nonthaburi province, on the outskirts of Bangkok February 14, 2015. Ten Thai couples laid in the pink coffin starting 9:09 AM on Saturday during the wedding ceremony organised by the Buddhist temple on Valentine's Day. Couples believe laying briefly in the coffin will get rid of bad luck and usher happiness into their lives. (Photo by Damir Sagolj/Reuters)

A humanoid robot named Kansei, meaning “sensibility” in Japanese, makes a facial expression depicting “happiness”, next to the word “Love” during a demonstration at a laboratory of Meiji University's Robot and Science Institute in Kawasaki, south of Tokyo in this June 4, 2007 file photo. Three-fourths of robot installations over the next decade are expected to be concentrated in four areas: transportation equipment, including the automotive sector; computer and electronic products; electrical equipment and machinery. Labor costs have climbed in countries such as China that have been popular for outsourcing production, while technological advances for robots allow them to be more flexible and perform more tasks. (Photo by Yuriko Nakao/Reuters)

“Early morning in Mandawa, rural Rajasthan: it was the morning of Diwali and the streets were swept by smiling women in brightly coloured sarees as I took an early morning cup of chai. Celebrations started later, when darkness fell”. (Photo by Hamish Scott-Brown/Guardian Witness)