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-oxido-N'-[4-[(2-oxobenzo[cd]indol-1-yl)methyl]benzoyl]pyridin-1-ium-3-carbohydrazide into molecular formula.
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C25H18N4O4
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