You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[(4-bromo-2-ethyl-5-methylpyrazol-3-yl)methyl]-2-cyclopropyl-5,5-dimethylpiperazine is the IUPAC name of a molecule. Please give its molecular formula.
user
C16H27BrN4
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