You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (5E)-3-ethyl-5-[[4-methoxy-3-[(2,4,6-trichlorophenoxy)methyl]phenyl]methylidene]-2-sulfanylidene-1,3-thiazolidin-4-one by IUPAC nomenclature, provide its molecular formula.
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C20H16Cl3NO3S2
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