You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-(3-cyano-4,5,6,7-tetrahydro-1-benzothiophen-2-yl)-2-[4-methyl-2-(1,2,4-triazol-4-yl)phenoxy]acetamide into molecular formula.
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C20H19N5O2S
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