A group of fashionable nonagenarians pose for a photo in Pengzhou, Sichuan, China on October 12, 2016. (Photo by Rex Features/Shutterstock)

Robot inventor Wu Yulu sits on a rickshaw driven by a robot which he invented in his village in rural Beijing's Tongzhou district, China, 17 November 2016. The 54-year-old Chinese farmer living in rural Beijing's Tongzhou district invented 63 robots in the past 30 years. Wu, who only received primary school education, plans to give up the agricultural work for his robot products. He regularly participates in exhibitions, transfers patent rights and teaches at the university to earn money. (Photo by Wu Hong/EPA)

A graffiti, portraying a woman, is seen in Medellin, Colombia on November 19, 2017. Mural graffitis from different artists, street art can be seen in almost every city on Earth, but street arts raw power and potential for change was felt by me most intensively in Medellins Comuna 13, previously one of Colombias most dangerous neighbourhoods, in fact Communa 13 was constant battleground between gangs, narcos, paramilitaries and the government, but today you would hardly recognise it. (Photo by Juancho Torres/Anadolu Agency/Getty Images)

People stand in front of an murals at Lodhi Art District in New Delhi on March 24, 2019. Visitors throng Lodhi colony which has murals by dozens of Indian and international artists. (Photo by Sajjad Hussain/AFP Photo)

A girl in an angel costume walks with her family past vegetable vendors in Havana, Cuba, Wednesday, April 10, 2019. (Photo by Ramon Espinosa/AP Photo)

In this Monday, June 10, 2019 photo, an Indian Rabha tribal Hindu priest pours traditional rice beer to a Rabha girl to perform rituals during Baikho festival at Pantan village, west of Gauhati, India. Every year, the community in India’s northeastern state of Assam celebrates the festival, to please a deity of wealth and ask for good rains and a good harvest. (Photo by Anupam Nath/AP Photo)

A man passes by a wall with graffiti in Beirut, Lebanon, on May 29, 2019. (Photo by Bilal Jawich/Xinhua News Agency/Alamy Live News)

An Indian Sadhu, or Hindu holy man, performs a yoga position on International Yoga Day at Kamakhya temple in Gauhati, India, Friday, June 21, 2019. (Photo by Anupam Nath/AP Photo)