You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-(cyclohexa-1,5-dien-1-ylamino)-8-methoxy-1-phenyl-1,6-naphthyridin-4-one;molecular hydrogen by IUPAC nomenclature, provide its molecular formula.
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C21H21N3O2
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