You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-(1,3-dibromo-4-oxo-5,6-dihydrocyclopenta[c]thiophen-6-yl)-4-(3,4-dihydro-1H-isoquinolin-2-yl)butanamide into molecular formula.
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C20H20Br2N2O2S
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