You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (5R)-3-[[(4-chlorophenyl)methyl-methylamino]methyl]-5-methyl-1-(4-methylphenyl)imidazolidine-2,4-dione into its molecular formula.
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C20H22ClN3O2
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