You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 7-[(1,5-dimethylpyrazol-4-yl)methyl]-3-(4-methoxyphenyl)-6,8-dihydro-5H-[1,2,4]triazolo[4,3-a]pyrazine into its molecular formula.
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C18H22N6O
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