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-(1H-benzimidazol-2-yl)-3-cyano-2-hydroxyprop-2-enyl] 2-[(3,4-dichlorophenyl)methylsulfanyl]acetate into molecular formula.
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C20H15Cl2N3O3S
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