You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-[[2-[(2,2-dimethyl-3-oxo-4H-1,4-benzoxazin-6-yl)amino]-5-fluoropyrimidin-4-yl]amino]benzamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H19FN6O3
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