You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (2S)-2-acetamido-N-[(2S)-1-amino-3-(3-bromophenyl)-1-oxopropan-2-yl]-3-(4-fluorophenyl)propanamide into its molecular formula.
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C20H21BrFN3O3
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