You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (3S)-1-(2,3-dihydroxy-1,4,4a,5,6,7,8,8a-octahydronaphthalen-1-yl)-3-methyl-2,4,4a,5,8,8a-hexahydro-1H-naphthalene-2,3-diol into molecular formula.
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C21H32O4
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