You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (1S,9S)-11-[2-(1H-benzimidazol-2-ylsulfanyl)acetyl]-7,11-diazatricyclo[7.3.1.02,7]trideca-2,4-dien-6-one into its molecular formula.
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C20H20N4O2S
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