You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (3R,3aR,5S,6S,7aR)-6-ethenyl-3,6-dimethyl-5-prop-1-en-2-yl-3,3a,4,5,7,7a-hexahydro-1-benzofuran-2-one into molecular formula.
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C15H22O2
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