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 1-[(2R)-2-[(2R)-1-[(3-fluoro-4-methoxyphenyl)methyl]pyrrolidin-2-yl]pyrrolidin-1-yl]propan-1-one into its molecular formula.
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C19H27FN2O2
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