There are 6 shapes on a 8x8 grid. Which shape is closest to the gray trapezoid in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: gray trapezoid at (0, 0)
Distance from target shape to green rectangle at (2, 4): 6
Distance from target shape to yellow trapezoid at (5, 3): 8
Distance from target shape to purple square at (3, 1): 4
Distance from target shape to brown square at (3, 3): 6
Distance from target shape to pink square at (4, 4): 8
Closest shape is the purple square at (3, 1) with distance 4</think>

<answer>(3, 1)</answer>