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What is the molecular formula of the compound with this IUPAC name 2-[(4-fluorophenyl)methyl]-8-(1-methylcyclopropanecarbonyl)-4,6,7,9,10,10a-hexahydro-3H-pyrazino[1,2-d][1,4]diazepin-1-one ?
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C20H26FN3O2
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