You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 3-[7-(2,5-diazabicyclo[2.2.1]heptan-2-yl)-4-fluoro-3-oxo-1H-isoindol-2-yl]piperidine-2,6-dione by IUPAC nomenclature, provide its molecular formula.
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C18H19FN4O3
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