You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (3R,4S)-N-(2,3-difluorophenyl)-4-(3-fluoro-5-methylphenyl)-2-oxopyrrolidine-3-carboxamide into its molecular formula.
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C18H15F3N2O2
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