You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 3-[[4-(4-methoxyphenyl)piperazin-1-yl]methyl]-5a,9-dimethyl-3a,4,5,9b-tetrahydro-3H-benzo[g][1]benzofuran-2,8-dione into molecular formula.
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C26H32N2O4
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