You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 3,4,4a,5,6,7,8,8a-octahydro-1H-isoquinolin-2-yl-[3-methyl-1-(2-methylpropyl)thieno[2,3-c]pyrazol-5-yl]methanone into its molecular formula.
user
C20H29N3OS
assistant