You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-(2-amino-2-phenylethyl)-6-[(2-chloro-6-fluorophenyl)methyl]-4-(2-fluorophenyl)-5-methylpyridazin-3-one by IUPAC nomenclature, provide its molecular formula.
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C26H22ClF2N3O
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