You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2S)-N-[1-(cyclobutadienyl)-6-propan-2-ylbenzimidazol-2-yl]-2,3-dimethylbutanamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H25N3O
assistant