You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 3-[[(3S)-1-[4-(dimethylamino)but-2-enoyl]pyrrolidin-3-yl]amino]-5-[2-(methylamino)pyridin-4-yl]-1H-pyridin-2-one into its molecular formula.
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C21H28N6O2
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