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 4-[(2S)-1-[(3S)-1,1-dioxothiolan-3-yl]-4-hydroxy-5-oxo-3-(thiophene-2-carbonyl)-2H-pyrrol-2-yl]benzoate into molecular formula.
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C21H19NO7S2
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