You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[(1S)-1-(3-fluoro-4-methylphenyl)ethyl]-2-[4-(4-fluorophenyl)-5-oxo-1,2,4-triazol-1-yl]acetamide into its molecular formula.
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C19H18F2N4O2
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