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 1-(4-fluoro-3-nitrophenyl)-5-oxo-N-(5,6,7,8-tetrahydronaphthalen-1-yl)pyrrolidine-3-carboxamide into its molecular formula.
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C21H20FN3O4
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