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 [(3aR,7S,7aS)-7-ethyl-7-hydroxy-3,3a,4,5,6,7a-hexahydro-1H-isoindol-2-yl]-(8-methylimidazo[1,2-a]pyridin-2-yl)methanone into molecular formula.
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C19H25N3O2
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