You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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1-[(4-bromo-1-methylpyrrol-2-yl)methyl]-3-(2,2-dicyclopropylethyl)-1,2-dimethylguanidine The above is the IUPAC name of a molecule. Write its molecular formula.
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C17H27BrN4
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