You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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1-[8-[(1-ethylpyrazol-4-yl)methyl]-3-(hydroxymethyl)-3-methyl-2,8-diazaspiro[4.5]decan-2-yl]ethanone is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H30N4O2
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