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 4-[2-[(2'R,3R,4'S)-6-chloro-4'-(3-chlorophenyl)-2,6'-dioxospiro[1H-indole-3,3'-piperidine]-2'-yl]-4-iodophenoxy]benzoic acid into molecular formula.
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C31H21Cl2IN2O5
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