You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 7-fluoro-6-[1-[5-(1-methylpyrazol-4-yl)imidazo[4,5-b]pyrazin-3-yl]ethyl]quinoline into molecular formula.
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C20H16FN7
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