You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 4-methyl-6-[3-(4-propan-2-ylphenyl)-1,2,4-oxadiazol-5-yl]-1,4-benzoxazin-3-one into its molecular formula.
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C20H19N3O3
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