You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[1-(3-phenyl-[1,2,4]triazolo[4,3-b]pyridazin-6-yl)piperidin-3-yl]pyridine-3-carboxamide into molecular formula.
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C22H21N7O
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