In Metal Gear Solid 4 how do you get the patriot

you can use a cheat or beat the game on big boss hard or the boss extreme without dying once

To obtain The Patriot in Metal Gear Solid 4: Guns of the Patriots, you must obtain the Big Boss emblem, which requires completing the game on the Boss Extreme difficulty with no continues, no alerts, no use of recovery items, no use of special items (Stealth Camouflage and Bandana), and with a total game time of under five hours. Alternately, you can enter the password "pkhhnwhsjt" in the Extras menu.