You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (2,5-dichlorothiophen-3-yl)-[4-[(4-methoxyphenyl)methyl]-1,4-diazepan-1-yl]methanone by IUPAC nomenclature, provide its molecular formula.
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C18H20Cl2N2O2S
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