You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule [(3aR,8aS)-2,3,3a,4,5,7,8,8a-octahydro-1H-pyrrolo[3,4-d]azepin-6-yl]-(3-phenylthiophen-2-yl)methanone into molecular formula.
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C19H22N2OS
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