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Dmitri Shostakovich, the renowned Soviet composer, studied under the tutelage of Alexander Glazunov at the Leningrad Conservatory. Glazunov, a prominent Russian composer and conductor, was known for his mastery of orchestration and his adherence to traditional classical forms. Under Glazunov's guidance, Shostakovich developed his compositional skills and laid the foundation for his future success as one of the most significant composers of the 20th century.