You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name [(13S)-2,13-dimethyl-17-methylidene-7,8,9,11,12,14,15,16-octahydro-6H-cyclopenta[a]phenanthren-3-yl] trifluoromethanesulfonate into its molecular formula.
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C21H25F3O3S
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