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 N-(2,3-dihydro-1H-inden-2-yl)-2-(2,2-dimethylpropanoylamino)-N,5-dimethylthiophene-3-carboxamide into molecular formula.
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C21H26N2O2S
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