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 (2S,3S,3aS,6aR)-6'-chloro-3-(4-chlorothiophen-2-yl)spiro[1,3,3a,5,6,6a-hexahydropyrrolo[2,3-c]pyrrole-2,3'-1H-indole]-2',4-dione into molecular formula.
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C17H13Cl2N3O2S
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