There are 2 shapes on a 9x9 grid. Which shape is closest to the purple rectangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: purple rectangle at (6, 8)
Distance from target shape to yellow right_triangle at (6, 4): 4
Closest shape is the yellow right_triangle at (6, 4) with distance 4</think>

<answer>(6, 4)</answer>