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 methyl 2-[[1-[(4-chlorophenyl)methyl]-5-methylpyrazol-3-yl]carbamothioylamino]-4-ethyl-5-methylthiophene-3-carboxylate into molecular formula.
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C21H23ClN4O2S2
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