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-[[(E)-(2-ethoxy-4-oxochromen-3-ylidene)methyl]amino]-N-(5-methyl-1,3,4-thiadiazol-2-yl)benzenesulfonamide into its molecular formula.
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C21H20N4O5S2
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