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-[[2-(2-aminopropanoylamino)-5-(diaminomethylideneamino)pentanoyl]amino]-4-carboxybutanoyl]amino]butanedioic acid into molecular formula.
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C18H31N7O9
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