You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[2,5-dioxo-1-(1-phenylethyl)-4-(trifluoromethyl)imidazolidin-4-yl]-3-methylbutanamide into molecular formula.
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C17H20F3N3O3
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