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 6a,9a-dichloro-6-(4-hydroxyphenyl)-8-methyl-1,3,7,9-tetraoxo-3a,4,6,10,10a,10b-hexahydroisoindolo[5,6-e]isoindole-2-carboxamide into molecular formula.
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C22H19Cl2N3O6
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