3-Pyridinemethanesulfonic acid, 5-[2-[5-[[4-chloro-6-[(4-sulfophenyl)amino]-1,3,5-triazin-2-yl]amino]-2-sulfophenyl]diazenyl]-1-ethyl-1,6-dihydro-2-hydroxy-4-methyl-6-oxo-, potassium sodium salt (1:?:?)