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 3-[[3-[3-fluoro-3-(3-methylphenyl)cyclobutyl]-1,2,4-oxadiazol-5-yl]methyl]pyrido[2,3-d]pyrimidin-4-one into molecular formula.
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C21H18FN5O2
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