You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[2-(diethylamino)-2-[4-(trifluoromethyl)phenyl]ethyl]-3-ethyl-2-[(2-methylpyrazol-3-yl)methyl]guanidine is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H31F3N6
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