There are 5 shapes on a 8x8 grid. Which shape is closest to the purple 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: purple square at (3, 7)
Distance from target shape to yellow trapezoid at (6, 4): 6
Distance from target shape to orange rectangle at (0, 6): 4
Distance from target shape to gray rectangle at (6, 0): 10
Distance from target shape to green square at (6, 6): 4
Closest shape is the orange rectangle at (0, 6) with distance 4</think>

<answer>(0, 6)</answer>