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-(2-fluorophenyl)-N-[2-[[2-(4-fluorophenyl)acetyl]amino]ethyl]-1,3-thiazole-5-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C20H17F2N3O2S
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