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What is the molecular formula of the molecule identified by (5E,6E)-5-ethylidene-4-hydroxy-1-methyl-3-[5-oxo-4-(pyridin-4-yliminomethyl)-1,2-dihydropyrazol-3-yl]-6-prop-2-enylidenepyridin-2-one ?
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C20H19N5O3
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