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system
Provide the molecular formula for the IUPAC named substance [(1S)-3,4-dihydro-1H-isochromen-1-yl]-[(3S)-3-(5-pyridin-3-yl-1,3,4-oxadiazol-2-yl)pyrrolidin-1-yl]methanone .
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C21H20N4O3
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