You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (2aR,4aR,7aS,7bS)-2,2,4a,7a-tetramethyl-2a,3,4,7b-tetrahydro-1H-cyclobuta[e]inden-5-one into molecular formula.
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C15H22O
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