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 3-amino-4-cyano-1-(6-oxo-5H-benzo[b][1,4]benzoxazepin-8-yl)pyrrole-2-carboxylate into molecular formula.
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C20H14N4O4
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