You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-(2,5-dimethylphenyl)-N-methyl-N-(2-methylpropyl)-6-oxo-4,5-dihydropyridazine-3-carboxamide into its molecular formula.
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C18H25N3O2
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