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 [2-[(2R)-2-ethylpiperidin-1-yl]-2-oxoethyl] 5-chloro-1-(4-fluorophenyl)-3-methylpyrazole-4-carboxylate into molecular formula.
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C20H23ClFN3O3
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