A certain geometric solid is obtained by removing a quadrangular prism from a cube. Its three-view drawing is shown in the figure. If the side length of each small square on the grid paper is 1, then the volume of this geometric solid is $\_\_\_\_$.
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A certain geometric solid is obtained by removing a quadrangular prism from a cube. Its three-view drawing is shown in the figure. If the side length of each small square on the grid paper is 1, then the volume of this geometric solid is $\_\_\_\_$.