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What is the molecular formula of the molecule identified by (2R)-N-[(R)-(3-chloro-4,5-difluorophenyl)-[6-(2,2,2-trifluoroethoxy)pyridin-3-yl]methyl]-2-methyl-3-oxopiperazine-1-carboxamide ?
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C20H18ClF5N4O3
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