Pumpkin Pie from Fresh Pumpkin

Homemade Pumpkin Puree from 1 to 2 small sugar pumpkins (see notes), about 4 cups
1 can sweetened condensed milk (14-ounce)
1/2 cup heavy cream
2 tablespoons cornstarch
2 tablespoons molasses
2 tablespoons canola oil
1 tablespoon ground cinnamon
1 teaspoon ground ginger
1/4 teaspoon salt
3 large eggs
1 unbaked 9 inch pie crust