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 N-tert-butyl-2-[2,4-dichloro-6-[[(2-oxo-1,3-dihydrobenzimidazol-5-yl)amino]methyl]phenoxy]acetamide into molecular formula.
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C20H22Cl2N4O3
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