You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 3-(4-fluorophenyl)-1-[4-(trifluoromethyl)phenyl]-5,6,7,8-tetrahydro-4H-pyrazolo[3,4-b]azepine into molecular formula.
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C20H17F4N3
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