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 ethyl 3-[5-ethoxy-3-(2-imidazol-1-ylethyl)-2,3-dihydroindol-1-yl]propanoate is given. What is its corresponding molecular formula?
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C20H27N3O3
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