You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (3aS,4R,7S,7aR)-2-(3,5-dichlorophenyl)-4,7-dimethyl-3a,5,6,7a-tetrahydro-4,7-epoxyisoindole-1,3-dione into molecular formula.
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C16H15Cl2NO3
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