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 N-[[5-(2-chloropyridin-3-yl)-4-fluoro-1H-pyrrol-3-yl]methyl]-1-(2,4-dimethoxyphenyl)-N-methylmethanamine into its molecular formula.
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C20H21ClFN3O2
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