You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-(4-bromo-3-methylphenyl)-1-(4-methylphenyl)sulfonyl-3,6-dihydro-2H-pyridine-4-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C20H21BrN2O3S
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