You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 2-[(4-chloro-2-fluorophenyl)methylsulfanyl]-N-[3-(2,3-dihydroindol-1-yl)propyl]acetamide is given. What is its corresponding molecular formula?
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C20H22ClFN2OS
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