You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (Z)-2-cyano-N-(1,5-dimethyl-3-oxo-2-phenylpyrazol-4-yl)-3-(4-fluorophenyl)prop-2-enamide into molecular formula.
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C21H17FN4O2
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