You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 4-(3-methoxyphenyl)-1-methyl-6-(pyridin-2-ylmethyl)-4,7-dihydro-3H-pyrrolo[3,4-d]pyrimidine-2,5-dione into its molecular formula.
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C20H20N4O3
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