You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2,6-dimethyl-N-[2-(6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepin-3-yl)ethyl]quinoline-3-carboxamide into molecular formula.
user
C21H25N5O
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