You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule ethyl 2-[5-[2-(3,4-difluorophenyl)acetyl]-6,7-dihydro-4H-pyrazolo[4,3-c]pyridin-1-yl]acetate .
user
C18H19F2N3O3
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