You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-ethyl-8-[(1-methylimidazol-2-yl)methyl]-4-(1-methylpyrazol-4-yl)-1,8-diazaspiro[4.5]decan-2-one by IUPAC nomenclature, provide its molecular formula.
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C19H28N6O
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