Using [Br-], Cc1c(O)ccc2c(-c3ccc(F)cc3)cc(=O)oc12 to produce Cc1c(Br)ccc2c(-c3ccc(F)cc3)cc(=O)oc12, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.