You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (5R)-7-[(1-butyltetrazol-5-yl)methyl]-3-propan-2-yl-1,3,7-triazaspiro[4.4]nonane-2,4-dione into molecular formula.
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C15H25N7O2
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