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 (5Z)-2-[4-[(4-fluorophenyl)methyl]piperazin-1-yl]-5-[(2-hydroxyphenyl)methylidene]-1,3-thiazol-4-one into molecular formula.
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C21H20FN3O2S
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