You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-benzyl-6-[(4-fluorophenyl)methyl]-7-oxo-[1,3]thiazolo[5,4-d]pyrimidine-2-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C20H15FN4O2S
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