You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(6S)-6-(4-chlorophenyl)-N-[(4-methylphenyl)methyl]-6,7-dihydro-4H-pyrazolo[5,1-c][1,4]oxazine-2-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H20ClN3O2
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