You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named N-[2-(cyclopropanecarbonyl)-3,4-dihydro-1H-isoquinolin-7-yl]-2-methylsulfanylpyridine-3-carboxamide is given. What is its corresponding molecular formula?
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C20H21N3O2S
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