You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule tert-butyl 3-[[[ethylamino-(3-methylpiperidin-1-yl)methylidene]amino]methyl]piperidine-1-carboxylate;hydroiodide into molecular formula.
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C20H39IN4O2
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