You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3,4,4a,5,6,7,8,8a-octahydro-1H-isoquinolin-2-yl-(3-amino-2,6-difluorophenyl)methanone is the IUPAC name of a molecule. Please give its molecular formula.
user
C16H20F2N2O
assistant