You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2'S,3S,4'S)-6-chloro-2'-(3-chloro-2-fluorophenyl)-4'-(2,2-dimethylpropyl)-N-(1-methylsulfonylpiperidin-4-yl)-2-oxospiro[1H-indole-3,3'-pyrrolidine]-1'-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C29H35Cl2FN4O4S
assistant