You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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2-[3-(3-bromo-1,2,4-triazol-1-yl)-1-adamantyl]-5-[(4-chlorophenyl)methyl]-1,3,4-oxadiazole is the IUPAC name of a molecule. Please give its molecular formula.
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C21H21BrClN5O
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