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system
What is the molecular formula of the molecule identified by 1-[3-(1-methylpyrazol-4-yl)-1'-(1,3-thiazole-4-carbonyl)spiro[5,6-dihydroimidazo[1,2-a]pyrazine-8,4'-piperidine]-7-yl]ethanone ?
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C20H23N7O2S
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