You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 1-(4-chlorophenyl)-1',6'-dimethylspiro[1,3-diazinane-5,3'-2,4-dihydroquinoline]-2,4,6-trione into molecular formula.
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C20H18ClN3O3
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