You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl (2R)-7-[(1,5-dimethylpyrazole-3-carbonyl)amino]-2-methyl-3-oxo-4H-1,4-benzoxazine-2-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
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C18H20N4O5
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