You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-[[5-(4-chlorophenyl)-4-ethyl-1,2,4-triazol-3-yl]sulfanyl]-N-(pyridin-2-ylmethyl)acetamide into molecular formula.
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C18H18ClN5OS
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