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 benzene;N-(3,4-difluorophenyl)-6,7,8,9-tetrahydro-5H-pyrrolo[1,2-a]azepine-8-carboxamide into molecular formula.
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C22H22F2N2O
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