You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (6R)-8-[(3-tert-butyl-1H-pyrazol-5-yl)methyl]-2-(cyclopropylmethyl)-2,8-diazaspiro[5.5]undecan-3-one by IUPAC nomenclature, provide its molecular formula.
user
C21H34N4O
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