You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 4-[(8-bromo-[1,2,4]triazolo[1,5-a]pyridin-2-yl)amino]-N-methyl-N-(1-methylpiperidin-4-yl)benzamide;methane by IUPAC nomenclature, provide its molecular formula.
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C21H27BrN6O
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