You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-(3,4-dihydro-2H-1,5-benzodioxepin-7-yl)-3-[2-(dimethylamino)-2-(3-methoxyphenyl)ethyl]-2-methylguanidine;hydroiodide is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H31IN4O3
assistant