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 N-[5-[8-amino-6-(fluoromethyl)-5H-imidazo[1,2-a]pyrazin-6-yl]-2-(difluoromethyl)phenyl]-5-chloro-3-fluoro-6-methylpyridine-2-carboxamide is given. What is its corresponding molecular formula?
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C21H17ClF4N6O
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