You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 1-[1-(5-chloro-2-methoxyphenyl)pyrrolidin-3-yl]-3-[2-(4-methoxyphenyl)ethyl]urea is given. What is its corresponding molecular formula?
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C21H26ClN3O3
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