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 (4R)-4-[1-[2-(4-chlorophenoxy)ethyl]benzimidazol-2-yl]-1-(2,6-dimethylphenyl)pyrrolidin-2-one into molecular formula.
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C27H26ClN3O2
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