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system
Provide the molecular formula for the IUPAC named substance 1-[4-[(8S)-2-cyclopropyl-8-(2-methylpropyl)-6,8-dihydro-5H-[1,2,4]triazolo[1,5-a]pyrazine-7-carbonyl]piperidin-1-yl]ethanone .
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C20H31N5O2
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