You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 4-chloro-2-(2,4-difluorophenyl)-5-[4-(piperidine-1-carbonyl)piperidin-1-yl]pyridazin-3-one is given. What is its corresponding molecular formula?
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C21H23ClF2N4O2
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