You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-[(3aS,9bR)-6-methoxy-1,3,3a,4,5,9b-hexahydrobenzo[e]isoindol-2-yl]acetonitrile into its molecular formula.
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C15H18N2O
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