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 6-bromo-N-[(4,6-dimethyl-2-oxo-1H-pyridin-3-yl)methyl]-3-methyl-N-propan-2-yl-2H-indazole-4-carboxamide into molecular formula.
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C20H23BrN4O2
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