You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named methyl (8S,12R)-17-methoxy-8,12-dimethyl-4-propan-2-yl-21-azapentacyclo[12.7.0.02,7.08,13.015,20]henicosa-1(14),2(7),3,5,15(20),16,18-heptaene-12-carboxylate by IUPAC nomenclature, provide its molecular formula.
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C28H33NO3
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