Preheat the oven to 350°F (175°C).In a large mixing bowl, combine the mashed sweet potatoes, granulated sugar, and brown sugar. Mix until smooth.Add the evaporated milk, eggs, vanilla extract, cinnamon, nutmeg, and salt. Mix well until all ingredients are fully combined.Pour the sweet potato mixture into the unbaked pie crust, spreading it evenly.Bake in the preheated oven for 45-50 minutes, or until the filling is set and the top is slightly golden.Allow the pie to cool before slicing and serving.