You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 2-[5-chloro-2-(4-prop-1-en-2-ylpiperazin-1-yl)pyridin-4-yl]-1-methylbenzimidazole is given. What is its corresponding molecular formula?
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C20H22ClN5
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