You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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1-[2-(1-hydroxyethyl)-2,5-dihydro-1H-pyrrolo[2,3-b]pyrazin-7-yl]-2,2-dimethylpropan-1-one is the IUPAC name of a molecule. Please give its molecular formula.
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C13H19N3O2
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