You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (4E)-4-[[5-(2-hydroxy-5-nitrophenyl)furan-2-yl]methylidene]-5-methyl-2-(2,3,4,5,6-pentafluorophenyl)pyrazol-3-one by IUPAC nomenclature, provide its molecular formula.
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C21H10F5N3O5
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