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system
Name the molecular formula for the molecule established as 2-[2-chloro-4-[(E)-2-(5-cyano-4-methyl-6-oxo-1H-pyridazin-3-yl)ethenyl]-6-ethoxyphenoxy]-N,N-dimethylacetamide using the IUPAC nomenclature.
user
C20H21ClN4O4
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