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-(2,4-dichlorophenyl)-2-(3-methylpiperidin-1-yl)-4,7-dioxo-3,5,6,8-tetrahydropyrido[2,3-d]pyrimidine-5-carboxamide .
user
C20H21Cl2N5O3
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