You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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3-[[2,6-difluoro-4-(2-methoxypyridin-4-yl)phenyl]methyl]pyrido[3,4-d]pyrimidin-4-one is the IUPAC name of a molecule. Please give its molecular formula.
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C20H14F2N4O2
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