You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 5-(3-chlorophenyl)-3-(4-chlorophenyl)-2-phenyl-3a,6a-dihydro-3H-pyrrolo[3,4-d][1,2]oxazole-4,6-dione by IUPAC nomenclature, provide its molecular formula.
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C23H16Cl2N2O3
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