You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name (6E)-9-methyl-6-[(4-methylphenyl)hydrazinylidene]-2,3,4,7,8,9-hexahydro-1H-pyrido[2,1-b]quinazolin-11-one into its molecular formula.
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C20H24N4O
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