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 2-butyl-2-[9-[(5-ethylthiophen-2-yl)methyl]-1-methyl-1,4,9-triazaspiro[5.5]undecan-3-yl]cyclohexane-1,4-dione into molecular formula.
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C26H41N3O2S
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