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 2-[[5-(4-methoxyphenyl)-1,3,4-oxadiazol-2-yl]sulfanyl]-1-(2-methyl-3,4-dihydro-2H-1,5-benzothiazepin-5-yl)ethanone into molecular formula.
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C21H21N3O3S2
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