A ballet dancer stretches backstage during Nacho Duato's “The Nutcracker” at the Mikhailovsky Theatre in St. Petersburg, Russia November 21, 2015. For theatregoers in St Petersburg, Nacho Duato's “The Nutcracker” demonstrates the global appeal of a Christmas classic. When the curtain rises at the Mikhailovsky Theatre, among the oldest opera and ballet houses in Russia, it's the culmination of hundreds of hours of toil and sweat by dancers, costume makers, set designers and musicians playing the famous score by Pyotr Tchaikovsky. (Photo by Grigory Dukor/Reuters)

American film and theater actress, singer and dancer Shirley MacLaine. (Photo by Philippe Halsman)

Margaret Morris dancers exercising on the sands at Saint-Idesbald. (Photo by Fox Photos/Getty Images). August 1929

Two traditional folk dancers performing in Teheran, Iran. (Photo by Keystone Features/Getty Images). 25th January 1961

A dancer performs as visitors take pictures at an auto show in Tianjin, China April 28, 2016. (Photo by Reuters/Stringer)

Dancers perform during La Paz Fashion Week in La Paz, Bolivia, February 7, 2019. (Photo by David Mercado/Reuters)

A man walks with a giant rake during carnival celebrations in Zubieta January 27, 2015. Bell carrying dancers known as Joaldunak from Zubieta and neighbouring Ituren visit each other's villages performing a ritual dance to ward off evil spirits and awaken the coming spring. Alongside the dancers, villagers dress in bizarre and frightening costumes to harass and scare visitors. (Photo by Vincent West/Reuters)

People wearing bear furs perform during a festival of New Year ritual dances attended by hundreds in Comanesti, northern Romania, Wednesday, December 30 2015. In pre-Christian rural traditions, dancers wearing colored costumes or animal furs, toured from house to house in villages singing and dancing to ward off evil, in the present the tradition has moved to Romania's cities too, where dancers travel to perform the ritual for money. (Photo by Vadim Ghirda/AP Photo)