You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 4-fluoro-2-[5-[[(2S,3R)-2-fluoro-8-azabicyclo[3.2.1]octan-3-yl]-methylamino]pyrazin-2-yl]-5-(triazol-1-yl)phenol by IUPAC nomenclature, provide its molecular formula.
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C20H21F2N7O
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