Blackberry Swirl Pie

1 pie crust, unbaked
3/4 c. sugar
1/8 tsp salt
1-8 oz carton sour cream
3 Tbsp flour
3 c. fresh blackberries or 1-16 oz pkg frozen

Preheat oven to 450. Let berries stand at room temp for 15 min. Meanwhile prepare pastry and line pastry with double thickness of foil. Bake 8 min. Remove foil. Bake 4 min or til lightly browned. Cool on rack. Reduce to 350. In bowl combine sour cream, sugar, flour, and salt. Add berried and stir to combine. Spoon into crust. Bake 25 min (50 for frozen berries). Remove foil. Bake 20 min more or til bubbly. Cool on rack for 2 hours. Serve or cover and refrigerate.