You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-(1-amino-2,3-dimethylbutan-2-yl)-2-oxo-1-(4-propan-2-ylphenyl)pyrrolidine-3-carboxamide into its molecular formula.
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C20H31N3O2
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