You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 1-ethyl-3-[6-[2-fluoro-5-[(5-methyl-4-oxo-3H-phthalazin-1-yl)methyl]phenyl]-1H-benzimidazol-2-yl]urea into molecular formula.
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C26H23FN6O2
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