You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-ethyl-5-(3-ethylthiophen-2-yl)-2-[5-(3-ethylthiophen-2-yl)thiophen-2-yl]thiophene The above is the IUPAC name of a molecule. Write its molecular formula.
user
C22H22S4
assistant