You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 3-[(5,8a-dimethyl-2-oxo-3,3a,7,8,9,9a-hexahydrobenzo[f][1]benzofuran-3-yl)methylamino]azepan-2-one into its molecular formula.
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C21H30N2O3
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