You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [1-[2-(difluoromethoxy)anilino]-1-oxopropan-2-yl] 4-(1,3-benzothiazol-2-yl)butanoate by IUPAC nomenclature, provide its molecular formula.
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C21H20F2N2O4S
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