You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 7-chloro-N-(2,6-dimethylphenyl)-2,3-dihydro-1H-cyclopenta[b]quinoline-9-carboxamide is given. What is its corresponding molecular formula?
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C21H19ClN2O
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