You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
7-(3,4-dichlorophenyl)-N,5-dimethyl-N-phenyl-4,7-dihydropyrazolo[1,5-a]pyrimidine-6-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H18Cl2N4O
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