You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 2-(2,3-dihydro-1H-inden-1-yl)-1-(6-methyl-1,3-dihydropyrrolo[3,4-c]pyridin-2-yl)ethanone into molecular formula.
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C19H20N2O
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