Katie Rose Hobbs and Kirsten Elizabeth Pobjoy of British Aerosuperbatics Wingwalking Team perform ballet in the air during Huangguoshu Waterfalls Flight Conference on August 3, 2018 in Anshun, Guizhou Province of China. Huangguoshu Waterfalls Flight Conference including 18 aircraft from seven aerobatic teams from all over the world kicked off on Friday. (Photo by VCG via Getty Images)

MiG-15 jet fighters are pictured in Kucova Air Base in Kucova, Albania on October 3, 2018. Albania retired its 224 Soviet- and Chinese-made MiGs in 2005, and since 2009 NATO neighbors Italy and Greece monitor its airspace. That led to economic decline in and around Kucova, which was called “Stalin City” during the era of Communist rule. (Photo by Florion Goga/Reuters)

Students from St Andrews University are covered in foam as they take part in the traditional Raisin Weekend in the Lower College Lawn, at St Andrews in Scotland on October 22, 2018. The “raisin weekend” stems from a gift of raisins (now flour and foam) traditionally given by a first year student to their academic “parents” in gratitude for their guidance. (Photo by Russell Cheyne/Reuters)

Fans dressed up in costume await the cast members on the red carpet at the world premiere of the film "The Avengers: Endgame" in Los Angeles, California, April 22, 2019. (Photo by Mario Anzuoni/Reuters)

Dancers are warming up backstage during the Tango Dancing Tournament at the XIII International Tango Festival in Medellin, Colombia, on June 18, 2019. The Tango Festival takes place between the 16th and 24th of June. (Photo by Joaquin Sarmiento/AFP Photo)

Male and female bodybuilders prepare backstage to compete during the Asia Pacific Bodybuilding Championships 2019 in Bangkok, Thailand, 17 August 2019. Hundreds of bodybuilders from Asia Pacific countries are set to flex their muscles to compete in the contest. (Photo by Rungroj Yongrit/EPA/EFE)

Emily Hicks (not pictured) of Charleston holds her dog Murphy along the waterfront ahead of the arrival of Hurricane Dorian in Charleston, South Carolina, U.S., September 4, 2019. (Photo by Randall Hill/Reuters)

A mahout sits between elephants which are participating in festivities marking the annual harvest festival of Onam at a temple on the outskirts of Kochi, India, September 11, 2019. (Photo by Sivaram V/Reuters)