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 (3R,5S)-5-methyl-3-[[5-[(2-methylphenoxy)methyl]-4-phenyl-1,2,4-triazol-3-yl]sulfanyl]oxolan-2-one into molecular formula.
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C21H21N3O3S
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