You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named ethyl 2'-amino-5-chloro-1'-(2,4-dichlorophenyl)-2,5'-dioxospiro[1H-indole-3,4'-7,8-dihydro-6H-quinoline]-3'-carboxylate by IUPAC nomenclature, provide its molecular formula.
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C25H20Cl3N3O4
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