You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 5-methyl-5-(4-methylphenyl)-3-[[5-(4-methylphenyl)-1,3,4-oxadiazol-2-yl]methyl]imidazolidine-2,4-dione into its molecular formula.
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C21H20N4O3
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