You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[[3,5-dimethyl-4-(2,2,2-trifluoroethoxy)phenyl]methyl-methylamino]-N-methyl-N-phenylacetamide by IUPAC nomenclature, provide its molecular formula.
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C21H25F3N2O2
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