You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-amino-4,4-bis(butylsulfanyl)-6-(3,4-dichlorophenyl)-3-azabicyclo[3.1.0]hex-2-ene-1,5-dicarbonitrile into its molecular formula.
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C21H24Cl2N4S2
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