You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule N-[5-[[4-[5-cyano-6-[[(3R)-oxolan-3-yl]amino]pyridin-3-yl]pyrimidin-2-yl]amino]pyridin-2-yl]acetamide into molecular formula.
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C21H20N8O2
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