You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-(5-bromo-2-pyrazol-1-ylphenyl)-2-[2-(methylsulfanylmethyl)benzimidazol-1-yl]acetamide by IUPAC nomenclature, provide its molecular formula.
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C20H18BrN5OS
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