You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-[ethyl(2-pyridin-4-ylethyl)amino]-1-(3-methylphenyl)-4-(4-nitrophenyl)pyrrole-2,5-dione is the IUPAC name of a molecule. Please give its molecular formula.
user
C26H24N4O4
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