You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 2-[[6-[(2R)-2-methylpyrrolidin-1-yl]-4-pyrrolidin-3-ylpyridin-2-yl]amino]pyridine-4-carbonitrile;hydrochloride is given. What is its corresponding molecular formula?
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C20H25ClN6
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