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 N'-[2-(2-cyanophenoxy)acetyl]-3-(3,4-dihydro-2H-1,5-benzodioxepin-7-yl)prop-2-enehydrazide into its molecular formula.
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C21H19N3O5
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