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 (5E)-5-[(2-chloro-6-fluorophenyl)methylidene]-3-(1,5-dimethyl-3-oxo-2-phenylpyrazol-4-yl)-2-sulfanylidene-1,3-thiazolidin-4-one into molecular formula.
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C21H15ClFN3O2S2
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