You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 5-[(2E,5Z)-4-imino-2-(1,2-oxazol-3-yl)nona-2,5-dien-5-yl]imino-3,3-dimethyl-4-propan-2-ylidenepyrrolidin-2-one into its molecular formula.
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C21H28N4O2
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