You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [10-chloro-4a-(3-methoxyphenyl)-3,4,5,6,11,11a-hexahydro-1H-pyrido[4,3-b]carbazol-2-yl]-phenylmethanone by IUPAC nomenclature, provide its molecular formula.
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C29H27ClN2O2
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