There are 3 shapes on a 8x8 grid. Which shape is closest to the pink 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: pink right_triangle at (1, 0)
Distance from target shape to blue rectangle at (5, 5): 9
Distance from target shape to red right_triangle at (1, 7): 7
Closest shape is the red right_triangle at (1, 7) with distance 7</think>

<answer>(1, 7)</answer>