You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[[2-[(4aR,8aR)-3,4,4a,5,6,7,8,8a-octahydro-2H-quinolin-1-yl]-3-fluorophenyl]methyl]ethanamine into molecular formula.
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C18H27FN2
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