You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(E)-1-[2-[2-[2-[2-(2-hydroxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]-4-phenylbut-3-en-2-ol is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H32O7
assistant