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 N-(3-chloro-6-fluoro-2H-indazol-5-yl)-4-(4-chlorophenyl)-6-methyl-2-oxo-3,4-dihydro-1H-pyridine-5-carboxamide into molecular formula.
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C20H15Cl2FN4O2
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