You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (Z)-N,N'-ditert-butyl-N'-[(1,3-ditert-butyl-1,3,2-diazaphosphol-2-yl)phosphanyl]ethene-1,2-diamine into molecular formula.
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C20H42N4P2
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