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 (3-chloro-1-benzothiophen-2-yl)-[4-(4-ethoxy-1,3-benzothiazol-2-yl)piperazin-1-yl]methanone into molecular formula.
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C22H20ClN3O2S2
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