There are 3 shapes on a 4x4 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 (2, 1)
Distance from target shape to yellow rectangle at (0, 3): 4
Distance from target shape to orange square at (0, 1): 2
Closest shape is the orange square at (0, 1) with distance 2</think>

<answer>(0, 1)</answer>