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system
Name the molecular formula for the molecule established as 2-[[1-[5-(trifluoromethyl)pyridin-2-yl]pyrrolidin-2-yl]methyl]-7,8-dihydro-5H-thiopyrano[4,3-c]pyridazin-3-one using the IUPAC nomenclature.
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C18H19F3N4OS
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