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 (5aR,9bS)-3,3a-dihydroxy-3-(hydroxymethyl)-5a,9-dimethyl-4,5,6,7,8,9b-hexahydrobenzo[g][1]benzofuran-2-one is given. What is its corresponding molecular formula?
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C15H22O5
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