You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 5-chloro-1-[(2,6-dichlorophenyl)methyl]-N-[(3,4-dimethoxyphenyl)methyl]-3-methylpyrazole-4-carboxamide into molecular formula.
user
C21H20Cl3N3O3
assistant