There are 4 shapes on a 9x9 grid. Which shape is closest to the purple 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: purple rectangle at (8, 2)
Distance from target shape to cyan right_triangle at (6, 8): 8
Distance from target shape to yellow trapezoid at (4, 1): 5
Distance from target shape to green right_triangle at (1, 8): 13
Closest shape is the yellow trapezoid at (4, 1) with distance 5</think>

<answer>(4, 1)</answer>