You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-[[5-(2-fluorophenyl)-4-methyl-1,2,4-triazol-3-yl]sulfanyl]-N-[2-(4-methoxyphenyl)ethyl]acetamide into its molecular formula.
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C20H21FN4O2S
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