You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [2-[4-chloro-3-(trifluoromethyl)phenyl]-6-(5-ethyl-2-methylpyrazol-3-yl)-3-hydroxyphenyl] acetate by IUPAC nomenclature, provide its molecular formula.
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C21H18ClF3N2O3
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