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-[2-[[2-[2-[(2-aminoacetyl)amino]propanoylamino]acetyl]amino]propanoylamino]-3-hydroxypropanoic acid by IUPAC nomenclature, provide its molecular formula.
user
C13H23N5O7
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