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 3-[3-(1,3,4,6,7,8,9,9a-octahydropyrido[1,2-a]pyrazine-2-carbonyl)-2-methoxyanilino]-4-(2-chloro-3-fluoroanilino)cyclobut-3-ene-1,2-dione into its molecular formula.
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C26H26ClFN4O4
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