You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 2,3,4,6,7,8,9,9a-octahydro-1H-quinolizine;N'-(4-chloro-3-fluorophenyl)-N-methyloxamide .
user
C18H25ClFN3O2
assistant