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-benzyl-6-oxo-N-[2-(6-oxo-3-phenylpyridazin-1-yl)ethyl]pyridazine-3-carboxamide into molecular formula.
user
C24H21N5O3
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