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Can you give the molecular formula of the molecule N-[(1S)-1-(4-chloro-3-fluorophenyl)ethyl]-2-[8-(4-methylpiperazin-1-yl)-3-oxo-[1,2,4]triazolo[4,3-a]pyrazin-2-yl]acetamide ?
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C20H23ClFN7O2
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