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What is the molecular formula of the molecule identified by (1R,3S,4S)-N-[(1S)-1-cyano-2-[2-fluoro-4-(6-oxo-3H-pyridin-3-yl)phenyl]ethyl]-2-azabicyclo[2.2.1]heptane-3-carboxamide ?
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C21H21FN4O2
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