You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 5-[2-[3-methoxy-6-(6-piperazin-1-ylpyridin-3-yl)pyridin-2-yl]ethynyl]imidazolidine-2,4-dione into its molecular formula.
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C20H20N6O3
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