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-chlorophenyl)methyl]-4-(5,7-dimethyl-4-oxo-3-phenylpyrrolo[3,4-d]pyridazin-6-yl)butanamide into molecular formula.
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C25H25ClN4O2
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