You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[[5-amino-2-[[2-[(2,4-diamino-4-oxobutanoyl)amino]-4-methylpentanoyl]amino]-5-oxopentanoyl]amino]-4-methylpentanoic acid by IUPAC nomenclature, provide its molecular formula.
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C21H38N6O7
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