You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [3-(cyanomethyl)-4-oxoquinazolin-2-yl]methyl 2-[(1R,2R,4R)-2-bicyclo[2.2.1]heptanyl]acetate into its molecular formula.
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C20H21N3O3
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