You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name (3-bromopyrazolo[1,5-a]pyrimidin-2-yl)-[4-[(3-fluorophenyl)methyl]piperazin-1-yl]methanone into its molecular formula.
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C18H17BrFN5O
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