You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-[[5-[1-(2-chloro-4-fluorophenoxy)ethyl]-4-ethyl-1,2,4-triazol-3-yl]sulfanyl]-N-(2-nitrophenyl)acetamide into its molecular formula.
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C20H19ClFN5O4S
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