You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 4-[[[4-(4-methylanilino)-6-morpholin-4-yl-1,3,5-triazin-2-yl]hydrazinylidene]methyl]benzene-1,3-diol by IUPAC nomenclature, provide its molecular formula.
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C21H23N7O3
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