There are 5 shapes on a 9x9 grid. Which shape is closest to the purple 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: purple trapezoid at (2, 1)
Distance from target shape to pink right_triangle at (3, 5): 5
Distance from target shape to brown square at (5, 8): 10
Distance from target shape to red square at (1, 5): 5
Distance from target shape to gray square at (3, 1): 1
Closest shape is the gray square at (3, 1) with distance 1</think>

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