You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 9-[4-(4-fluorophenyl)piperazin-1-yl]-N,N,3-trimethyl-6-oxo-5H-benzo[b][1,4]benzoxazepine-8-sulfonamide by IUPAC nomenclature, provide its molecular formula.
user
C26H27FN4O4S
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