You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [(3R,5S,8R,9S,10S,13S,14R,17E)-17-hydroxyimino-10,13-dimethyl-1,2,3,4,5,6,7,8,9,11,12,14,15,16-tetradecahydrocyclopenta[a]phenanthren-3-yl] acetate by IUPAC nomenclature, provide its molecular formula.
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C21H33NO3
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