You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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N-[(Z)-(4-bromo-2-ethylpyrazol-3-yl)methylideneamino]-4-butan-2-ylbenzenesulfonamide is the IUPAC name of a molecule. Please give its molecular formula.
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C16H21BrN4O2S
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