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 1-(3-bromophenyl)-N-methyl-N-(1,2,3,4-tetrahydroisoquinolin-7-ylmethyl)methanamine is given. What is its corresponding molecular formula?
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C18H21BrN2
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