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 methyl 4-[2-[3-(1H-indol-3-yl)propanoylamino]-1,3-thiazol-4-yl]-1H-pyrrole-2-carboxylate into its molecular formula.
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C20H18N4O3S
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