You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 1-[(3aR,6S,7aS)-3a,6-dimethoxy-3,4,5,6,7,7a-hexahydro-2H-indol-1-yl]-4-phenylbutane-1,4-dione is given. What is its corresponding molecular formula?
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C20H27NO4
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