You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named N-[3-(difluoromethoxy)-4-methoxyphenyl]-2,3,4,5-tetrahydro-1H-3-benzazepine-7-carboxamide;hydrochloride by IUPAC nomenclature, provide its molecular formula.
user
C19H21ClF2N2O3
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