You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [4-(4-fluorophenyl)-1,4-diazepan-1-yl]-(4-methoxy-5-methylsulfanyl-2-nitrophenyl)methanone into its molecular formula.
user
C20H22FN3O4S
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