You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name (E)-3-[3-[[4-chloro-3,5-bis(difluoromethyl)pyrazol-1-yl]methyl]-4-methoxyphenyl]-1-(1-ethylpyrazol-3-yl)prop-2-en-1-one into its molecular formula.
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C21H19ClF4N4O2
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