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-amino-3-methylpentanoyl)amino]-3-hydroxybutanoyl]amino]-5-oxopentanoyl]amino]-4-methylsulfanylbutanoic acid by IUPAC nomenclature, provide its molecular formula.
user
C20H37N5O7S
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