You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (3S,5R)-N-[3-(1H-benzimidazol-2-yl)propyl]-7-(2-methylpropanoyl)-1-oxo-2,7-diazaspiro[4.4]nonane-3-carboxamide by IUPAC nomenclature, provide its molecular formula.
user
C22H29N5O3
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