You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name (4Z)-1-butyl-4-[(3,4-dichlorophenyl)-hydroxymethylidene]-5-(5-methylfuran-2-yl)pyrrolidine-2,3-dione into its molecular formula.
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C20H19Cl2NO4
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