You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-cyano-1-[(3R,4S)-6-cyano-3-hydroxy-2,2-dimethyl-3,4-dihydrochromen-4-yl]-2-(4-fluorophenyl)guanidine into its molecular formula.
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C20H18FN5O2
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