You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2E)-6-ethenyl-2-[(6-ethenyl-3-ethyl-1,3-benzothiazol-3-ium-2-yl)methylidene]-3-ethyl-1,3-benzothiazole;iodide is the IUPAC name of a molecule. Please give its molecular formula.
user
C23H23IN2S2
assistant