You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 4-[[(5Z)-5-benzylidene-2,4-dioxo-1,3-thiazolidin-3-yl]methyl]-N-(1,3-thiazol-2-yl)benzamide into its molecular formula.
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C21H15N3O3S2
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