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 (5R)-N-[(2,4-difluorophenyl)methyl]-2-(pyrrolidine-1-carbonyl)-4,5,6,7-tetrahydro-1-benzothiophene-5-carboxamide is given. What is its corresponding molecular formula?
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C21H22F2N2O2S
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