You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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6-(2-hydroxy-2-methylpropoxy)-4-(6-pyrrolidin-1-ylpyridin-3-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile is the IUPAC name of a molecule. Please give its molecular formula.
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C21H23N5O2
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