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 (4Z)-4-[(4-chlorophenyl)-hydroxymethylidene]-1-(pyridin-3-ylmethyl)-5-thiophen-2-ylpyrrolidine-2,3-dione into molecular formula.
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C21H15ClN2O3S
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