There are 5 shapes on a 8x8 grid. Which shape is closest to the yellow 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: yellow rectangle at (5, 4)
Distance from target shape to orange trapezoid at (6, 3): 2
Distance from target shape to cyan right_triangle at (0, 2): 7
Distance from target shape to purple rectangle at (5, 5): 1
Distance from target shape to red right_triangle at (4, 2): 3
Closest shape is the purple rectangle at (5, 5) with distance 1</think>

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