1 (20 oz.) can crushed pineapple, in own juice
1 (4 oz.) pkg. or 4 serving size pkg. sugar free instant pistachio pudding, dry
1 env. whipped topping mix, whipped
1 (10") baked pie shell or graham cracker crust

Mix whipped topping and dry pudding and the can of pineapple, with juice, all together. Pour into pie shell and top with whipped topping if desired. Chill and serve.