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What is the molecular formula of the compound with this IUPAC name (3'aR,5R,5'R,5'aR,8'aR,9'S,9'aS)-9'-hydroxy-5',8'a-dimethylspiro[3,4-dihydropyrazole-5,1'-3a,4,5,5a,9,9a-hexahydroazuleno[6,7-b]furan]-2',8'-dione ?
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C16H20N2O4
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