You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule spiro[1,3-dithiolane-2,12'-5,8-dithiahexacyclo[8.7.0.02,15.03,14.04,9.011,16]heptadecane] into molecular formula.
user
C17H22S4
assistant