You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 2-[5-[(4-ethylphenyl)methylidene]-2,4-dioxo-1,3-thiazolidin-3-yl]-N-[2-(trifluoromethyl)phenyl]acetamide into molecular formula.
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C21H17F3N2O3S
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