You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-(1,2,3,5,6,7,8,8a-octahydroindolizin-1-yl)-8-thia-4,6-diazatricyclo[7.5.0.02,7]tetradeca-1(9),2,4,6-tetraen-3-amine is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H26N4S
assistant