You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-[N-(dimethylsulfamoyl)-2,5-dimethylanilino]-1-[(2R)-2-methyl-2,3-dihydroindol-1-yl]ethanone into its molecular formula.
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C21H27N3O3S
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