You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1S,6R)-3-(3,5-difluorophenyl)sulfonyl-7-[(3-methoxyphenyl)methyl]-3,7-diazabicyclo[4.2.0]octane is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H22F2N2O3S
assistant