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 1-(3,4-dihydro-1H-isoquinolin-2-yl)-2-[3-(2-fluorophenyl)-2,5-dimethyl-1,2,4-oxadiazol-5-yl]ethanone into molecular formula.
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C21H22FN3O2
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