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 5-cyano-N-[1-(2,2-difluoroethyl)-5-fluoro-6-oxopyridin-3-yl]-4-(2-pyridin-4-ylethynyl)thiophene-2-carboxamide into molecular formula.
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C20H11F3N4O2S
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