You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-[3-(2-chlorophenyl)-2,5-dimethyl-1,2,4-oxadiazol-5-yl]-1-(3,4-dihydro-1H-isoquinolin-2-yl)ethanone into its molecular formula.
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C21H22ClN3O2
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