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Provide the molecular formula for the IUPAC named substance 8-(1-ethylpyrazole-4-carbonyl)-2-[(4-fluorophenyl)methyl]-4,6,7,9,10,10a-hexahydro-3H-pyrazino[1,2-d][1,4]diazepin-1-one .
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C21H26FN5O2
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