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-(ethylamino)-2-methyl-4-(1-methyl-2,3,4,4a,5,7,8,8a-octahydro-1,6-naphthyridin-6-yl)butanamide into molecular formula.
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C16H32N4O
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