You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[5-(dimethylsulfamoyl)-2,3-dimethylphenyl]-3-(3-oxo-1,4-benzothiazin-4-yl)propanamide into its molecular formula.
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C21H25N3O4S2
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