You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (4aS,5S)-3-(4-fluorophenyl)-N-(2-methylpropyl)-1,2,4,4a,5,6-hexahydropyrazino[1,2-a]quinoline-5-carboxamide into molecular formula.
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C23H28FN3O
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