You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule (5S,10bR)-9-chloro-2-(4-methoxyphenyl)-5-thiophen-2-yl-5,10b-dihydro-1H-pyrazolo[1,5-c][1,3]benzoxazine ?
user
C21H17ClN2O2S
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