You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 4-[3-[(2R)-2-(3-chloropyridin-2-yl)oxypropyl]-2-methylimidazo[4,5-b]pyridin-5-yl]pyridine-2,6-diamine into molecular formula.
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C20H20ClN7O
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