You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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5-(2-chloro-4-fluorophenyl)-3-[[1-(3-fluorophenyl)pyrazol-3-yl]methyl]-5-methylimidazolidine-2,4-dione is the IUPAC name of a molecule. Please give its molecular formula.
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C20H15ClF2N4O2
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