There are 5 shapes on a 7x7 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 (0, 3)
Distance from target shape to green rectangle at (4, 2): 5
Distance from target shape to brown rectangle at (5, 5): 7
Distance from target shape to pink right_triangle at (4, 4): 5
Distance from target shape to gray right_triangle at (5, 4): 6
Closest shape is the green rectangle at (4, 2) with distance 5</think>

<answer>(4, 2)</answer>