You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-(3-acetamidophenyl)-2-[5-methoxy-2-[(5-methyl-1,3,4-thiadiazol-2-yl)sulfanylmethyl]pyridin-4-yl]oxyacetamide into its molecular formula.
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C20H21N5O4S2
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