You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 3-(3,5,6,7,8,9-hexahydro-1H-pyrrolo[3,4-h][2]benzazepin-2-yl)piperidine-2,6-dione by IUPAC nomenclature, provide its molecular formula.
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C17H21N3O2
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