You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 4-[4-[[3-(4-methoxyphenyl)-[1,2,4]triazolo[4,3-b]pyridazin-6-yl]oxy]phenyl]butan-2-one into molecular formula.
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C22H20N4O3
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