You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (2S,3R,8aS)-3-(2,2-dimethylpropanoyl)-2-(furan-2-yl)-1',3'-dioxospiro[3,8a-dihydro-2H-indolizine-1,2'-indene]-6-carbonitrile into molecular formula.
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C26H22N2O4
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