You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-(2-ethoxyphenyl)-5-[1-(5-phenyl-1,3,4-oxadiazol-2-yl)ethylsulfanyl]-1,3,4-thiadiazol-2-amine into its molecular formula.
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C20H19N5O2S2
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