You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(3,4-difluorophenyl)-[2-[4-(2-pyrrolidin-1-ylethoxy)phenyl]-1-benzothiophen-3-yl]methanone is the IUPAC name of a molecule. Please give its molecular formula.
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C27H23F2NO2S
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