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 1-[4-(4-bromo-3-methylphenyl)piperazin-1-yl]-2-[4-chloro-3-methyl-5-(trifluoromethyl)pyrazol-1-yl]ethanone is given. What is its corresponding molecular formula?
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C18H19BrClF3N4O
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