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 (5R,8R,9S)-8-benzoyl-9-hydroxy-3-methyl-2-(5-methylfuran-2-yl)-1,7-dioxaspiro[4.4]non-2-ene-4,6-dione is given. What is its corresponding molecular formula?
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C20H16O7
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