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-[3-methoxy-3-(phenoxymethyl)pyrrolidin-1-yl]-4-(2-methylimidazol-1-yl)butan-1-one is given. What is its corresponding molecular formula?
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C20H27N3O3
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