You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-methyl-N-(2-methylpyridin-3-yl)-3-[4-(trifluoromethyl)phenyl]imidazo[1,2-a]pyrazine-6-carboxamide into its molecular formula.
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C21H16F3N5O
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