You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 6-methyl-7-oxo-1-[[3-(3-phenyl-3-azabicyclo[3.1.0]hexan-6-yl)-1,2,4-oxadiazol-5-yl]methyl]pyrazolo[4,3-d]pyrimidine-3-carbonitrile by IUPAC nomenclature, provide its molecular formula.
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C21H18N8O2
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