Students at the Cuba's National Ballet School (ENB) watch a class from outside the classroom in Havana, Cuba, October 12, 2016. Catherine Conley, the first American full-time student at Cuba's prestigious National Ballet School, hopes to gain an edge back home by learning the powerful Cuban style with its dazzling turns and jumps. (Photo by Alexandre Meneghini/Reuters)

Nubian women sell traditional handicrafts at the Nubian Gharb Suheil village, near Aswan south of Egypt, October 1, 2015. For half a century, Egypt's Nubians have patiently lobbied the government in Cairo for a return to their homelands on the banks of the upper Nile, desperate to reclaim territory their ancestors first cultivated 3,000 years ago. (Photo by Mohamed Abd El Ghany/Reuters)

Aeroflot employees with a puppy at the canine service of Aeroflot at Sheremetyevo International Airport in Moscow Region, Russia on October 2, 2020, that has started to train service dogs to detect COVID-19 in people. (Photo by Vladimir Gerdo/TASS)

Dancers at the Windmill Theatre in London, England practice a routine wearing gas masks and hard-hats with their costumes, 1940. (Photo by Hulton Archive/Getty Images)

The Blue Man Group performs on stage during a media preview ahead of their show in Singapore on March 31, 2016. Blue Man Group was started by three friends in New York in 1991 as a way to celebrate the human spirit through music, science, art and theater. (Photo by Roslan Rahman/AFP Photo)

Farmer Zhang Xianping rides his pig "Big Precious" during an interview with the media, in Zhangjiakou, Hebei province, China, November 2, 2015. Zhang, a pig breeder, instead of killing it, decided to keep the two-year-old "Big Precious" as pet when its weight reached 600 kg, according to local media. (Photo by Reuters/China Daily)

Filipinos cross a swelling river in Las Pinas city, south of Manila, Philippines, 09 July 2015. According to the Philippines State weather forecast, heavy rainfall is expected in Metro Manila and nearby provinces due to an enhanced Southwest Monsoon and Tropical Storm Linfa, Typhoon Chan-hom and Typhoon Nangka which are lining up across the Pacific Ocean. (Photo by Francis R. Malasig/EPA)

A group of students sit on top of a bus at Kemusu street in Boyolali, Central Java of Indonesia, March 20, 2015 in this picture taken by Antara Foto. (Photo by Yusuf Nugroho/Reuters/Antara Foto)