You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule N-(3,5-dichloropyridin-4-yl)-2-(2-oxo-4-phenyl-4,4a-dihydro-3H-cyclopenta[g]chromen-3-yl)acetamide .
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C25H18Cl2N2O3
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