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 (4S,4aS,8aR)-1-[[3-(methylsulfanylmethyl)-1,2,4-oxadiazol-5-yl]methyl]-4-phenyl-2,3,4a,5,6,7,8,8a-octahydroquinolin-4-ol into molecular formula.
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C20H27N3O2S
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