You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (2'R,3S,3'R,5'R)-N-[2-(4-acetylpiperazin-1-yl)ethyl]-6-chloro-3'-(3-chlorophenyl)-5'-(2,2-dimethylpropyl)-5-fluoro-2-oxospiro[1H-indole-3,4'-pyrrolidine]-2'-carboxamide into molecular formula.
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C31H38Cl2FN5O3
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