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 2-(2,4-dibromophenoxy)-N-[(E)-(2,5-dimethyl-1-phenylpyrrol-3-yl)methylideneamino]acetamide into molecular formula.
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C21H19Br2N3O2
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