You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (1S,5R)-6-benzyl-3-(3,5-difluoropyridine-2-carbonyl)-3,6-diazabicyclo[3.2.2]nonan-7-one into molecular formula.
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C20H19F2N3O2
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