There are 5 shapes on a 8x8 grid. Which shape is closest to the pink square 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 square at (5, 4)
Distance from target shape to yellow square at (4, 0): 5
Distance from target shape to red right_triangle at (7, 3): 3
Distance from target shape to green square at (5, 5): 1
Distance from target shape to gray rectangle at (0, 1): 8
Closest shape is the green square at (5, 5) with distance 1</think>

<answer>(5, 5)</answer>