You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (1-methylimidazol-4-yl)-[(8R)-5-methyl-8-(pyridin-3-ylmethoxymethyl)-2,5-diazaspiro[3.5]nonan-2-yl]methanone into its molecular formula.
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C20H27N5O2
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