You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 4-bromo-N-[1-(7-methoxy-1-benzofuran-2-yl)ethyl]-5-propan-2-yl-1H-pyrazole-3-carboxamide into its molecular formula.
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C18H20BrN3O3
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