You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 5-[2-(4-acetyl-1,4-diazepan-1-yl)-2-oxoethyl]-3,3-dimethyl-1H-indol-2-one by IUPAC nomenclature, provide its molecular formula.
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C19H25N3O3
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