You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
5-[(5-chloro-2-oxo-1,3-dihydroindol-3-yl)methyl]-N-[2-(dimethylamino)ethyl]-2,4-dimethyl-1H-pyrrole-3-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H25ClN4O2
assistant