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 2-acetyl-6-amino-8-(2-fluoro-5-methoxyphenyl)-1,3,8,8a-tetrahydroisoquinoline-5,7,7-tricarbonitrile into molecular formula.
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C21H18FN5O2
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