You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-fluoro-N-[1-[5-[2-oxo-2-(pyridin-3-ylamino)ethyl]sulfanyl-4-prop-2-enyl-1,2,4-triazol-3-yl]ethyl]benzamide into molecular formula.
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C21H21FN6O2S
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