Blackberry pie

So my mom bought a ton of blackberries. And what are you supposed to do with them other than make a pie. So I found an easy recipe online for them from allrecipes.com . Here is the link and the recipe itself. http://allrecipes.com/Recipe/Blackberry-Pie-I/Detail.aspx
INGREDIENTS

* 4 cups fresh blackberries
* 1/2 cup white sugar
* 1/2 cup all-purpose flour
* 1 recipe pastry for a 9 inch double crust pie
* 2 tablespoons milk
* 1/4 cup white sugar
DIRECTIONS

1. Combine 3 1/2 cups berries with the sugar and flour. Spoon the mixture into an unbaked pie shell. Spread the remaining 1/2 cup berries on top of the sweetened berries, and cover with the top crust. Seal and crimp the edges. Brush the top crust with milk, and sprinkle with 1/4 cup sugar.
2. Bake at 425 degree F (220 degrees C) for 15 minutes. Reduce the temperature of the oven to 375 degrees F (190 degrees C), and bake for an additional 20 to 25 minutes.