You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named N-benzyl-5-(3-methylbutanoyl)-1,5,10,11-tetrazatricyclo[7.3.0.03,7]dodeca-9,11-diene-12-carboxamide is given. What is its corresponding molecular formula?
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C21H27N5O2
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