There are 3 shapes on a 7x7 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 (5, 0)
Distance from target shape to blue rectangle at (1, 6): 10
Distance from target shape to gray rectangle at (1, 2): 6
Closest shape is the gray rectangle at (1, 2) with distance 6</think>

<answer>(1, 2)</answer>