You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named dimethyl 3-[(Z)-2-[2,3-bis(methoxycarbonyl)phenyl]ethenyl]-2-cyanopyrrole-3,4-dicarboxylate is given. What is its corresponding molecular formula?
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C21H18N2O8
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