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 2-(5-bromo-1-benzofuran-2-yl)ethyl 2-(2,4-dioxo-1,3-diazaspiro[4.5]decan-3-yl)acetate into molecular formula.
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C20H21BrN2O5
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