You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name methyl 2-[(3S)-5-(4-bromophenyl)-7-ethoxy-2-oxo-1,3-dihydro-1,4-benzodiazepin-3-yl]acetate into its molecular formula.
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C20H19BrN2O4
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