You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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N-(3,4-dimethylphenyl)-2-morpholin-4-yl-6,8-dihydro-5H-pyrido[3,4-d]pyrimidine-7-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
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C20H25N5O2
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