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-[[4-(dimethylamino)-6-(1-methyl-5-oxopyrrolidin-3-yl)pyrimidin-2-yl]methyl]-N-methylcyclohexanecarboxamide into molecular formula.
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C20H31N5O2
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