You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[(4-cyano-2-fluorophenyl)methyl]-3-ethyl-1-methyl-1-[(1-methyl-3-propan-2-ylpyrazol-4-yl)methyl]guanidine is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H27FN6
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