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 7-methoxy-1-methyl-5-[3-(trifluoromethyl)phenyl]-2,3,4,4a,5,9b-hexahydroindeno[1,2-b]pyridine into molecular formula.
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C21H22F3NO
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