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 (2S)-2-[acetyl(methyl)amino]-2-(2-chloro-6-fluorophenyl)-N-[[2-(methoxymethyl)phenyl]methyl]acetamide is given. What is its corresponding molecular formula?
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C20H22ClFN2O3
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