There are 6 shapes on a 9x9 grid. Which shape is closest to the blue right_triangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: blue right_triangle at (6, 7)
Distance from target shape to red rectangle at (8, 7): 2
Distance from target shape to gray trapezoid at (0, 1): 12
Distance from target shape to green square at (2, 0): 11
Distance from target shape to purple rectangle at (1, 2): 10
Distance from target shape to orange trapezoid at (8, 8): 3
Closest shape is the red rectangle at (8, 7) with distance 2</think>

<answer>(8, 7)</answer>